Talk:Rat Development

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Cite this page: Hill, M.A. 2017 Embryology Rat Development. Retrieved November 19, 2017, from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Rat_Development

original Rat page

10 Most Recent Papers

Note - This sub-heading shows an automated computer PubMed search using the listed sub-heading term. References appear in this list based upon the date of the actual page viewing. Therefore the list of references do not reflect any editorial selection of material based on content or relevance. In comparison, references listed on the content page and discussion page (under the publication year sub-headings) do include editorial selection based upon relevance and availability. (More? Pubmed Most Recent)


Rat Development

Yan Yang, Xu Zhang, Min Xu, Xin Wu, Feipeng Zhao, Chengzhi Zhao Quercetin attenuates collagen-induced arthritis by restoration of Th17/Treg balance and activation of Heme Oxygenase 1-mediated anti-inflammatory effect. Int. Immunopharmacol.: 2017, 54;153-162 PubMed 29149703

Patrick M Kochanek, Jessica S Wallisch, Hülya Bayır, Robert S B Clark Pre-clinical models in pediatric traumatic brain injury-challenges and lessons learned. Childs Nerv Syst: 2017, 33(10);1693-1701 PubMed 29149385

Chieh-Chih Shih, Hwong-Ru Hwang, Chi-I Chang, Huei-Meei Su, Pei-Chin Chen, Hsiao-Mei Kuo, Pei-Jyuan Li, Hui-Min David Wang, Kuan-Hao Tsui, Yu-Chi Lin, Shi-Ying Huang, Zhi-Hong Wen Anti-Inflammatory and Antinociceptive Effects of Ethyl Acetate Fraction of an Edible Red Macroalgae Sarcodia ceylanica. Int J Mol Sci: 2017, 18(11); PubMed 29149031

Tengfei Zhou, Guo Li, Shiyu Lin, Taoran Tian, Quanquan Ma, Qi Zhang, Sirong Shi, Changyue Xue, Wenjuan Ma, Xiaoxiao Cai, Yunfeng Lin Electrospun Poly (3-Hydroxybutyrate-Co-4-Hydroxybutyrate)/Graphene Oxide Scaffold: Enhanced Properties and Promoted in Vivo Bone Repair in Rats. ACS Appl Mater Interfaces: 2017; PubMed 29148704

Alejandro Barriga-Rivera, Veronica Tatarinoff, Nigel H Lovell, John W Morley, Gregg J Suaning Long-term anesthetic protocol in rats: feasibility in electrophysiology studies in visual prosthesis. Vet Ophthalmol: 2017; PubMed 29148158


Rat Embryology

Sezcan Mumusoglu, Volkan Turan, Hasan Uckan, Aysegul Suzer, Lale Karakoc Sokmensuer, Gurkan Bozdag The Impact of a Long-Acting Oral Sphingosine-1-Phosphate Analogue on Ovarian Aging in a Rat Model. Reprod Sci: 2017;1933719117741376 PubMed 29137549

Selçuk Yazıcı, Cansu Unden Ozcan, Adnan Adil Hismiogullari, Fatma Bahar Sunay, Teoman Ozcan, Emel Ataş Berksoy, Elif Aksoz Protective Effects of Quercetin on Necrotizing Enterocolitis in a Neonatal Rat Model. Am J Perinatol: 2017; PubMed 29132181

Kristina Curgali, Stefan Toth, Zuzana Jonecova, Milan Maretta, Theodoros Kalpakidis, Ivana Petriskova, Matus Kusnier, Jan Soltes, Martin Svana, Martin Caprnda, Delian Delev, Luis Rodrigo, Eva Mechirova, Peter Kruzliak Quercetin protects jejunal mucosa from experimental intestinal ischemia reperfusion injury by activation of CD68 positive cells. Acta Histochem.: 2017; PubMed 29129327

Anıl Özyurt, Çiğdem Elmas, Cemile Merve Seymen, Veysel Tuncay Peker, Bülent Altunkaynak, Mehmet Nadir Güngör Effects of Low-Level Laser Therapy With a Herbal Extract on Alveolar Bone Healing. J. Oral Maxillofac. Surg.: 2017; PubMed 29125929

Okan Ozkunt, Kerim Sariyilmaz, Halil Can Gemalmaz, Seren Gülsen Gürgen, Ulaş Yener, Fatih Dikici Investigation of efficacy of treatment in spinal cord injury: Erythropoietin versus methylprednisolone. J Orthop Surg (Hong Kong): 2017, 25(3);2309499017739481 PubMed 29121822


2013

Develop to term rat oocytes injected with heat-dried sperm heads

PLoS One. 2013 Nov 4;8(11):e78260. doi: 10.1371/journal.pone.0078260.

Lee KB, Park KE, Kwon IK, Tripurani SK, Kim KJ, Lee JH, Niwa K, Kim MK. Source The Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan.

Abstract

This study investigated the development of rat oocytes in vitro and in vivo following intracytoplasmic injection of heads from spermatozoa heat-dried at 50°C for 8 h and stored at 4°C in different gas phases. Sperm membrane and chromosome are damaged by the process of heat-drying. Oocyte activation and cleavage of oocytes were worse in oocytes injected with spermatozoa heat-dried and stored for 1 week than unheated, fresh spermatozoa, but in heat-dried spermatozoa, there were no differences in these abilities of oocytes between the samples stored in nitrogen gas and in air. The oocytes injected with heat-dried spermatozoa stored for 1 week could develop to the morula and blastocyst stages without difference between the samples stored in nitrogen gas and in air after artificial stimulation. Cleavage of oocytes and development of cleaved embryos were higher when heat-dried spermatozoa were stored for 3 and 6 months in nitrogen gas than in air. However, the ability of injected oocytes to develop to the morula and blastocyst stages was not inhibited even when heat-dried spermatozoa stored in both atmosphere conditions for as long as 6 months were used. When 2-cell embryos derived from oocytes injected with heads from spermatozoa heat-dried and stored for 1 week and 1 month were transferred, each 1 of 4 recipients was conceived, and the conceived recipients delivered 1 live young each. These results demonstrate that rat oocytes can be fertilized with heat-dried spermatozoa and that the fertilized oocytes can develop to term.

PMID 24223784

2012

Physiological characteristics and logistical considerations of the three most used animal models for nutritional intervention in early life

Francisco J Pérez-Cano, Àngels Franch, Cristina Castellote, Margarida Castell The suckling rat as a model for immunonutrition studies in early life. Clin. Dev. Immunol.: 2012, 2012;537310 PubMed 22899949

| PMC3415261 | Clin Dev Immunol.

Postnatal Animal Models Mouse Rat Pig
Pregnancy period (days) 18 – 21 21 – 23 110 – 118
Placenta type Discoidal, decidual
hemoendothelial choroidea
Discoidal, decidual
hemoendothelial choroidea
Epitheliochorial
Litter size 6 – 12 6 – 15 11 – 16
Birth weight (g) 0.5 – 1.5 3 – 5 900 – 1600
Weaning weight male/female (g) 18 – 25/16 – 25 55 – 90/45 – 80 6000 – 8000
Suckling period (days) 21–28 21 28–49
Solid diet beginning (days) 10 12 12 – 15
Puberty male/female (week) 4 – 6/5 6/6 – 8 20 – 28
Life expectancy (years) 1 - 2 2 - 3 14 – 18
PMID 13207763
Mouse Rat Pig
Pregnancy period (days) 18 – 21 21 – 23 110 – 118
Placenta type Discoidal, decidual
hemoendothelial choroidea
Discoidal, decidual
hemoendothelial choroidea
Epitheliochorial
Litter size 6 – 12 6 – 15 11 – 16
Birth weight (g) 0.5 – 1.5 3 – 5 900 – 1600
Weaning weight male/female (g) 18 – 25/16 – 25 55 – 90/45 – 80 6000 – 8000
Suckling period (days) 21–28 21 28–49
Solid diet beginning (days) 10 12 12 – 15
Puberty male/female (week) 4 – 6/5 6/6 – 8 20–28
Life expectancy (years) 1 - 2 2 - 3 14 – 18

Copyright © 2012 Francisco J. Pérez-Cano et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Cross-Species Genome Wide Expression Analysis during Pluripotent Cell Determination in Mouse and Rat Preimplantation Embryos

PLoS One. 2012;7(10):e47107. doi: 10.1371/journal.pone.0047107. Epub 2012 Oct 15.

Casanova EA, Okoniewski MJ, Cinelli P. Source Institute of Laboratory Animal Science, University of Zurich, Zurich, Switzerland.

Abstract

The transition between morula and blastocyst stage during preimplantation development represents the first differentiation event of embryogenesis. Morula cells undergo the first cellular specialization and produce two well-defined populations of cells, the trophoblast and the inner cell mass (ICM). Embryonic stem cells (ESCs) with unlimited self-renewal capacity are believed to represent the in vitro counterpart of the ICM. Both mouse and rat ESCs can be derived from the ICM cells, but their in vitro stability differs. In this study we performed a microarray analysis in which we compared the transcriptome of mouse and rat morula, blastocyst, and ICM. This cross-species comparison represents a good model for understanding the differences in derivation and cultivation of ESCs observed in the two species. In order to identify alternative regulation of important molecular mechanisms the investigation of differential gene expression between the two species was extended at the level of signaling pathways, gene families, and single selected genes of interest. Some of the genes differentially expressed between the two species are already known to be important factors in the maintenance of pluripotency in ESCs, like for example Sox2 or Stat3, or play a role in reprogramming somatic cells to pluripotency like c-Myc, Klf4 and p53 and therefore represent interesting candidates to further analyze in vitro in the rat ESCs. This is the first study investigating the gene expression changes during the transition from morula to blastocyst in the rat preimplantation development. Our data show that in the pluripotent pool of cells of the rat and mouse preimplantation embryo substantial differential regulation of genes is present, which might explain the difficulties observed for the derivation and culture of rat ESCs using mouse conditions.

PMID 23077551


2011

Toxicological pathology in the rat placenta

J Toxicol Pathol. 2011 Jun;24(2):95-111. Epub 2011 Jun 30.

Furukawa S, Hayashi S, Usuda K, Abe M, Hagio S, Ogawa I. Source Biological Research Laboratories, Nissan Chemical Industries, Ltd., 1470 Shiraoka, Minamisaitama, Saitama 349-0294, Japan.

Abstract

The placenta grows rapidly for a short period with high blood flow during pregnancy and has multifaceted functions, such as its barrier function, nutritional transport, drug metabolizing activity and endocrine action. Consequently, the placenta is a highly susceptible target organ for drug- or chemical-induced adverse effects, and many placenta-toxic agents have been reported. However, histopathological examination of the placenta is not generally performed, and the placental toxicity index is only the placental weight change in rat reproductive toxicity studies. The placental cells originate from the trophectoderm of the embryo and the endometrium of the dam, proliferate and differentiate into a variety of tissues with interaction each other according to the development sequence, resulting in formation of a placenta. Therefore, drug- or chemical-induced placental lesions show various histopathological features depending on the toxicants and the exposure period, and the pathogenesis of placental toxicity is complicated. Placental weight assessment appears not to be enough to evaluate placental toxicity, and reproductive toxicity studies should pay more attention to histopathological evaluation of placental tissue. The detailed histopathological approaches to investigation of the pathogenesis of placental toxicity are considered to provide an important tool for understanding the mechanism of teratogenicity and developmental toxicity with embryo lethality, and could benefit reproductive toxicity studies.

PMID 22272049

Generation of germline-competent rat induced pluripotent stem cells

PLoS One. 2011;6(7):e22008. Epub 2011 Jul 15.

Hamanaka S, Yamaguchi T, Kobayashi T, Kato-Itoh M, Yamazaki S, Sato H, Umino A, Wakiyama Y, Arai M, Sanbo M, Hirabayashi M, Nakauchi H. Source Japan Science Technology Agency, Exploratory Research for Advanced Technology (ERATO), Nakauchi Stem Cell and Organ Regeneration Project, Tokyo, Japan.

Abstract BACKGROUND: Recent progress in rat pluripotent stem cell technology has been remarkable. Particularly salient is the demonstration that embryonic stem cells (ESCs) in the rat (rESCs) can contribute to germline transmission, permitting generation of gene-modified rats as is now done using mouse ESCs (mESCs) or mouse induced pluripotent stem cells (iPSCs; miPSCs). However, determinations of whether rat iPSCs (riPSCs) can contribute to germ cells are not published. Here we report the germline competency of riPSCs.

METHODOLOGY/PRINCIPAL FINDINGS: We generated riPSCs by transducing three mouse reprogramming factors (Oct3/4, Klf4, and Sox2) into rat somatic cells, followed by culture in the presence of exogenous rat leukemia inhibitory factor (rLIF) and small molecules that specifically inhibit GSK3, MEK, and FGF receptor tyrosine kinases. We found that, like rESCs, our riPSCs can contribute to germline transmission. Furthermore we found, by immunostaining of testis from mouse-rat interspecific chimeras with antibody against mouse vasa homolog, that riPSCs can contribute to embryonic development with chimera formation in mice (rat-mouse interspecific chimeras) and to interspecific germlines.

CONCLUSIONS/SIGNIFICANCE: Our data clearly demonstrate that using only three reprogramming factors (Oct3/4, Klf4, and Sox2) rat somatic cells can be reprogrammed into a ground state. Our generated riPSCs exhibited germline transmission in either rat-rat intraspecific or mouse-rat interspecific chimeras.

PMID 21789202

2010

Generation and characterization of a Tet-On (rtTA-M2) transgenic rat

http://www.ncbi.nlm.nih.gov/pubmed/20158911

BMC Dev Biol. 2010 Feb 16;10:17.

Sheng Y, Lin CC, Yue J, Sukhwani M, Shuttleworth JJ, Chu T, Orwig KE.

Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA. Abstract BACKGROUND: The tetracycline-inducible gene regulation system is a powerful tool that allows temporal and dose-dependent regulation of target transgene expression in vitro and in vivo. Several tetracycline-inducible transgenic mouse models have been described with ubiquitous or tissue-specific expression of tetracycline-transactivator (tTA), reverse tetracycline-transactivator (rtTA) or Tet repressor (TetR). Here we describe a Tet-On transgenic rat that ubiquitously expresses rtTA-M2 driven by the murine ROSA 26 promoter. RESULTS: The homozygous rat line (ROSA-rtTA-M2) generated by lentiviral vector injection, has a single integration site and was derived from the offspring of a genetic mosaic founder with multiple transgene integrations. The rtTA-M2 transgene integrated into an intron of a putative gene on chromosome 2 and does not appear to affect the tissue-specificity or expression of that gene. Fibroblasts from the ROSA-rtTA-M2 rats were transduced with a TetO7/CMV-EGFP lentivirus and exhibited doxycycline dose-dependent expression of the EGFP reporter transgene, in vitro. In addition, doxycycline-inducible EGFP expression was observed, in vivo, when the TetO7/CMV-EGFP lentivirus was injected into testis, kidney and muscle tissues of ROSA-rtTA-M2 rats. CONCLUSIONS: This conditional expression rat model may have application for transgenic overexpression or knockdown studies of gene function in development, disease and gene therapy.

PMID 20158911

Toxicological pathology in the rat placenta

J Toxicol Pathol. 2011 Jun;24(2):95-111. Epub 2011 Jun 30.

Furukawa S, Hayashi S, Usuda K, Abe M, Hagio S, Ogawa I. Source Biological Research Laboratories, Nissan Chemical Industries, Ltd., 1470 Shiraoka, Minamisaitama, Saitama 349-0294, Japan.

Abstract

The placenta grows rapidly for a short period with high blood flow during pregnancy and has multifaceted functions, such as its barrier function, nutritional transport, drug metabolizing activity and endocrine action. Consequently, the placenta is a highly susceptible target organ for drug- or chemical-induced adverse effects, and many placenta-toxic agents have been reported. However, histopathological examination of the placenta is not generally performed, and the placental toxicity index is only the placental weight change in rat reproductive toxicity studies. The placental cells originate from the trophectoderm of the embryo and the endometrium of the dam, proliferate and differentiate into a variety of tissues with interaction each other according to the development sequence, resulting in formation of a placenta. Therefore, drug- or chemical-induced placental lesions show various histopathological features depending on the toxicants and the exposure period, and the pathogenesis of placental toxicity is complicated. Placental weight assessment appears not to be enough to evaluate placental toxicity, and reproductive toxicity studies should pay more attention to histopathological evaluation of placental tissue. The detailed histopathological approaches to investigation of the pathogenesis of placental toxicity are considered to provide an important tool for understanding the mechanism of teratogenicity and developmental toxicity with embryo lethality, and could benefit reproductive toxicity studies.

PMID 22272049

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3234607

http://www.jstage.jst.go.jp/article/tox/24/2/24_95/_article


http://www.jstage.jst.go.jp/article/tox/24/2/95/_pdf

Determination of cell types and numbers during cardiac development in the neonatal and adult rat and mouse

Indroneal Banerjee, John W Fuseler, Robert L Price, Thomas K Borg, Troy A Baudino Determination of cell types and numbers during cardiac development in the neonatal and adult rat and mouse. Am. J. Physiol. Heart Circ. Physiol.: 2007, 293(3);H1883-91 PubMed 17604329


"We observed that the adult murine myocardium is composed of approximately 56% myocytes, 27% fibroblasts, 7% endothelial cells, and 10% vascular smooth muscle cells. Moreover, our morphometric and FACS data demonstrated similar percentages in the three regions examined. During murine neonatal cardiac development, we observed a marked increase in numbers of cardiac fibroblasts and a resultant decrease in percentages of myocytes in late neonatal development (day 15). ...Finally, FACS analyses of the rat heart during development displayed similar results in relation to increases in cardiac fibroblasts during development; however, cell populations in the rat differed markedly from those observed in the mouse."

1985

Embryonic development of the rat cerebellum. III. Regional differences in the time of origin, migration, and settling of Purkinje cells

Altman J, Bayer SA. J Comp Neurol. 1985 Jan 1;231(1):42-65. PMID 3968228

"The time of origin, site of origin, migratory path and settling pattern of the Purkinje cells of the cerebellar hemispheres, anterior vermis, and posterior vermis were investigated in thymidine radiograms and plastic-embedded materials from rat embryos ranging in age from 15 to 22 days. In the hemispheres there is a rostral-to-caudal cytogenetic gradient: the Purkinje cells of lobulus simplex, crus I, and crus II are produced earlier than the Purkinje cells of the paramedian lobule and paraflocculus, followed by the Purkinje cells of the flocculus. The Purkinje cells of the vermis, in general, are generated later than those of the hemispheres, and with a reverse gradient from caudal to rostral: the Purkinje cells of the posterior vermis (lobules X-VI) being produced ahead of the Purkinje cells of the anterior posteriorly directed wedge of early-produced Purkinje cells through the vermis. Evidence was obtained that the Purkinje cells of the hemispheres derive from the lateral cerebellar primordium capping the lateral recess of the fourth ventricle anteriorly. The Purkinje cells of the anterior vermis originate from the subisthmal cerebellar primordium medially lining the isthmal canal. The Purkinje cells of the posterior vermis originate in the postisthmal cerebellar primordium overlying the tela choroidea caudally. The young Purkinje cells migrate from the neuroepithelium to the surface of the cerebellum in a strictly caudal-to-rostral order, paralleling the spread of the EGL superficially from posteroventral to anterodorsal. This pattern is independent of the time of origin of Purkinje cells. In the posterior vermis the earliest-settling Purkinje cells of the uvula follow a short radial course, and a discrete Purkinje layer is formed 3 days after they are generated. In the anterior vermis the Purkinje cells of lobulus centralis, which follow an anterodorsal migratory course, are still settling on day E22, 7 days after their production, presumably awaiting the fusion of the cerebellar base anteriorly. The fissura prima forms medially at the interface region of Purkinje cells derived from the postisthmal and subisthmal cerebellar primordia. For 1-2 days after their settling, the Purkinje cells of the newly forming lobules can be distinguished by certain cytological criteria from the Purkinje cells in the more caudally-situated, earlier-settled lobules."
  • Embryonic development of the rat cerebellum. II. Translocation and regional distribution of the deep neurons. Altman J, Bayer SA. J Comp Neurol. 1985 Jan 1;231(1):27-41. PMID: 3968227
  • Embryonic development of the rat cerebellum. I. Delineation of the cerebellar primordium and early cell movements. Altman J, Bayer SA. J Comp Neurol. 1985 Jan 1;231(1):1-26. PMID: 3968224



Thalamus

  • Development of the rat thalamus: VI. The posterior lobule of the thalamic neuroepithelium and the time and site of origin and settling pattern of neurons of the lateral geniculate and lateral posterior nuclei. Altman J, Bayer SA. J Comp Neurol. 1989 Jun 22;284(4):581-601. PMID: 2768553
  • Development of the rat thalamus: V. The posterior lobule of the thalamic neuroepithelium and the time and site of origin and settling pattern of neurons of the medial geniculate body. Altman J, Bayer SA. J Comp Neurol. 1989 Jun 22;284(4):567-80. PMID: 2768552
  • Development of the rat thalamus: IV. The intermediate lobule of the thalamic neuroepithelium, and the time and site of origin and settling pattern of neurons of the ventral nuclear complex. Altman J, Bayer SA. J Comp Neurol. 1989 Jun 22;284(4):534-66. PMID: 2768551
  • Development of the rat thalamus: III. Time and site of origin and settling pattern of neurons of the reticular nucleus. Altman J, Bayer SA. J Comp Neurol. 1988 Sep 15;275(3):406-28. PMID: 3225345
  • Development of the rat thalamus: II. Time and site of origin and settling pattern of neurons derived from the anterior lobule of the thalamic neuroepithelium.

Altman J, Bayer SA. J Comp Neurol. 1988 Sep 15;275(3):378-405. PMID: 3225344

Precerebellar Nuclei

  • Development of the precerebellar nuclei in the rat: IV. The anterior precerebellar extramural migratory stream and the nucleus reticularis tegmenti pontis and the basal pontine gray. Altman J, Bayer SA. J Comp Neurol. 1987 Mar 22;257(4):529-52. PMID: 3693597
  • Development of the precerebellar nuclei in the rat: I. The precerebellar neuroepithelium of the rhombencephalon. Altman J, Bayer SA. J Comp Neurol. 1987 Mar 22;257(4):477-89. PMID: 3693594


The relationship of the birth date of rat sympathetic neurons to the target they innervate (p NA)

D. P. Chubb, C. R. Anderson Published Online: Feb 3 2010 10:35AM DOI: 10.1002/dvdy.22240 http://www3.interscience.wiley.com/journal/123272243/abstract?CRETRY=1&SRETRY=0


peak time of withdrawal from the cell cycle for sympathetic postganglionic neurons was calculated to be between E15.25 and E17.0 for all classes of sympathetic neuron

Type Pilomotor Cut Vaso Sudomotor Iridomotor Periosteal Thermomotor Secretomotor Musc vaso

Peak E15.27 E15.29 E15.42 E15.57 E15.65 E15.80 E16.35 E16.99


Microscopic anatomy of brachial plexus branches in Wistar rat

Anat Rec (Hoboken). 2007 May;290(5):477-85.

Santos AP, Suaid CA, Fazan VP, Barreira AA.

Department of Neurology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. Abstract In the present study, we analyze the morphology and morphometry of the lateral proper digital nerve of the third finger, and of the proximal and distal segments of the ulnar, median, and radial nerves, in Wistar rats 4 or 7 weeks old. The fascicular area and diameter were generally significantly greater in the proximal compared to distal segments and tended to be larger in 7-week-old compared to 4-week-old rats (e.g., median nerve area of 0.13 mm(2) for the proximal and 0.07 mm(2) for distal segments in 4-week-old rats, and 0.17 and 0.10 mm(2), respectively, for the proximal and distal segments of 7-week-old rats). The number of fascicles was significantly greater while the number of myelinated fibers was significantly less in the distal segments (e.g., 1,359 and 509 myelinated fibers, respectively, in the proximal and distal segments of the radial nerve 4-week-old rats). There was no significant difference in these parameters between the two age groups. The diameter of the myelinated fibers and their respective axons increased from 4 to 7 weeks of age (e.g., myelinated fiber diameter of 4.10 microm in 4-week-old animals and 4.7 microm in the ulnar nerve proximal segment of 7-week-old rats). The g-ratio regression line (axon diameter vs. fiber diameter quotient) was outlined for all the nerves studied here. Differences in myelinated fiber density were detected between the segments of the radial nerve, accompanying the number of myelinated fibers. Detailed knowledge of the microscopic anatomy of rat forelimb nerves provides control data for comparison with studies of experimentally induced neuropathies, which can shed more light on human neuropathies.

(c) 2007 Wiley-Liss, Inc. PMID: 17436315

Ovulation

Superovulatory response, oocyte spontaneous activation, and embryo development in WMN/Nrs inbred rats. Kito S, Yano H, Ohta Y, Tsukamoto S. Exp Anim. 2010;59(1):35-45. PMID: 20224168

Some Recent Findings

Generation and characterization of a Tet-On (rtTA-M2) transgenic rat. Sheng Y, Lin CC, Yue J, Sukhwani M, Shuttleworth JJ, Chu T, Orwig KE. BMC Dev Biol. 2010 Feb 16;10:17. PMID: 20158911

"This conditional expression rat model may have application for transgenic overexpression or knockdown studies of gene function in development, disease and gene therapy."

Sonic Hedgehog gene delivery to the rodent heart promotes angiogenesis via iNOS/netrin-1/PKC pathway. Ahmed RP, Haider KH, Shujia J, Afzal MR, Ashraf M. PLoS One. 2010 Jan 5;5(1):e8576. PMID: 20052412

"Reprogramming of stem cells with Shh maximizes their survival and angiogenic potential in the heart via iNOS/netrin-1/PKC signaling."