Puberty Development: Difference between revisions
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'''Links:''' [[Postnatal Development|Postnatal]] | [[Neonatal Development]] | [[Puberty Development]] | [[Genital_System_Development|Genital]] | [http://embryology.med.unsw.edu.au/Child/puberty.htm original page] | :'''Links:''' [[Postnatal Development|Postnatal]] | [[Neonatal Development]] | [[Puberty Development]] | [[Genital_System_Development|Genital]] | [http://embryology.med.unsw.edu.au/Child/puberty.htm original page] | ||
==Some Recent Findings== | ==Some Recent Findings== | ||
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The physiological process is initiated by the hypothalmus releasing gonadotropin releasing hormone (GnRH) which signals the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH) which in turn signals throughout the body sexual development. | The physiological process is initiated by the hypothalmus releasing gonadotropin releasing hormone (GnRH) which signals the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH) which in turn signals throughout the body sexual development. | ||
'''Links:''' [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.section.1058 Endocrinology - Puberty] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.1100 Endocrinology - Endocrine changes in puberty] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.chapter.972 Endocrinology - Gonad] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=cm.chapter.6480 Clinical Methods - The Adolescent Patient] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=cm.table.6485 Clinical Methods - Staging Criteria for Secondary Sexual Development] | [http://www.nichd.nih.gov/health/topics/Puberty.cfm NICHD - Puberty] | [http://www.ucsf.edu/sfshare/maledevelopment.html UCSF - Male Development] | | |||
:'''Links:''' [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.section.1058 Endocrinology - Puberty] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.1100 Endocrinology - Endocrine changes in puberty] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.chapter.972 Endocrinology - Gonad] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=cm.chapter.6480 Clinical Methods - The Adolescent Patient] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=cm.table.6485 Clinical Methods - Staging Criteria for Secondary Sexual Development] | [http://www.nichd.nih.gov/health/topics/Puberty.cfm NICHD - Puberty] | [http://www.ucsf.edu/sfshare/maledevelopment.html UCSF - Male Development] | | |||
== Precocious Puberty == | == Precocious Puberty == | ||
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Determined in boys by a lack of increase in testicular volume by the age of 14 years. In girls, no breast development by the age of 13.5 years and a lack of menstruation by the age of 16 years. There can also be a "pubertal arrest" where there is no progress in puberty over 2 year period. | Determined in boys by a lack of increase in testicular volume by the age of 14 years. In girls, no breast development by the age of 13.5 years and a lack of menstruation by the age of 16 years. There can also be a "pubertal arrest" where there is no progress in puberty over 2 year period. | ||
'''Links:''' [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.section.1104 Endocrinology - Delayed puberty] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.1105 Endocrinology - Definitions and causes of delayed puberty] | [http://kidshealth.org/teen/sexual_health/changing_body/delayed_puberty.html Nemours Foundation - Delayed Puberty] | |||
:'''Links:''' [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.section.1104 Endocrinology - Delayed puberty] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.1105 Endocrinology - Definitions and causes of delayed puberty] | [http://kidshealth.org/teen/sexual_health/changing_body/delayed_puberty.html Nemours Foundation - Delayed Puberty] | |||
== Kisspeptin == | == Kisspeptin == | ||
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The original discovery of the peptide was made by scientists located in Hershey, PA, USA and named the gene "Kiss1" after the "Hershey chocolate kiss". | The original discovery of the peptide was made by scientists located in Hershey, PA, USA and named the gene "Kiss1" after the "Hershey chocolate kiss". | ||
'''Links:''' [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=603286 OMIM - KISS1 METASTASIS SUPPRESSOR] | [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=604161 OMIM - G-protein-coupled receptor 54] | | |||
:'''Links:''' [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=603286 OMIM - KISS1 METASTASIS SUPPRESSOR] | [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=604161 OMIM - G-protein-coupled receptor 54] | | |||
== Gonadotropin Releasing Hormone (GnRH) == | == Gonadotropin Releasing Hormone (GnRH) == | ||
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GnRH increases during early puberty, followed by an increased pituitary responsiveness, then increasing sex steroid levels and then increased nocternal Luteinizing hormone (LH) secretion. | GnRH increases during early puberty, followed by an increased pituitary responsiveness, then increasing sex steroid levels and then increased nocternal Luteinizing hormone (LH) secretion. | ||
'''Links:''' [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.section.1061 Endocrinology - GnRH and the control of gonadotrophin synthesis and secretion] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.1062 Endocrinology - Synthesis of GnRH and its actions on pituitary gonadotrophs] | | |||
:'''Links:''' [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.section.1061 Endocrinology - GnRH and the control of gonadotrophin synthesis and secretion] | [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=endocrin.box.1062 Endocrinology - Synthesis of GnRH and its actions on pituitary gonadotrophs] | | |||
==Female Postnatal Ovary Growth== | ==Female Postnatal Ovary Growth== | ||
Revision as of 16:59, 4 January 2011
Introduction
These notes cover normal Postnatal Development during the puberty period which occurs mainly in the early teenage years. Triggers to puberty include neuroendocrine changes in hypothalamic expression of kisspeptin which is suggested in turn to change gonadotropin releasing hormone (GnRH) levels. (More? Kisspeptin | Gonadotropin Releasing Hormone | Endocrine Notes - Hypothalamus)
Male and female sexual differentiation giving the complete sexual phenotype involves two main phases.
- Primary, is the formation of an ovary or a testis from the bipotential gonad in the embryo.
- Secondary, is the development of the female and male phenotypes in response to hormones secreted by the ovaries and testes which occurs in the teen years during adolescence. This is initiated by the renewed expression of gonadotropin releasing hormone (GnRH) which is minimal in childhood.
Of general interest would be the timing differences between girls and boys when puberty commences (girls before boys). Early onset of puberty (precocious) occurs more frequently in girls than boys, in contrast late onset (delayed) occurs more frquently in boys than girls.
- Links: Postnatal | Neonatal Development | Puberty Development | Genital | original page
Some Recent Findings
|
Puberty
Can occur over a broad range of time and differently for each sex: girls (age 7 to 13) boys (age 9 to 15).
The physical characteristics that can be generally measured are: genital stage, pubic hair, axillary hair, menarche, breast, voice change and facial hair.
The physiological process is initiated by the hypothalmus releasing gonadotropin releasing hormone (GnRH) which signals the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH) which in turn signals throughout the body sexual development.
- Links: Endocrinology - Puberty | Endocrinology - Endocrine changes in puberty | Endocrinology - Gonad | Clinical Methods - The Adolescent Patient | Clinical Methods - Staging Criteria for Secondary Sexual Development | NICHD - Puberty | UCSF - Male Development |
Precocious Puberty
Premature development of the signs of puberty which can occur in both girls (before age 7 or 8) and in boys (before age 9).
Links: Endocrinology - Precocious sexual development | NICHD - Precocious Puberty | Nemours Foundation - Precocious Puberty | MedlinePlus - Obesity May Trigger Earlier Puberty for Girls | Time Magazine - Teens Before Their Time |
Delayed Puberty
Determined in boys by a lack of increase in testicular volume by the age of 14 years. In girls, no breast development by the age of 13.5 years and a lack of menstruation by the age of 16 years. There can also be a "pubertal arrest" where there is no progress in puberty over 2 year period.
- Links: Endocrinology - Delayed puberty | Endocrinology - Definitions and causes of delayed puberty | Nemours Foundation - Delayed Puberty
Kisspeptin
While the hypothalamic expression of gonadotropin releasing hormone (GnRH) is a known puberty trigger, it was not known what initiated the GnRH secretion. Recent research suggests that an earlier signal could come from increased neuronal and hypothalamic expression of a peptide family (kisspeptins) and their receptor (G protein-coupled receptor GPR54) in the hypothalamus. A single gene (Kiss1) encodes these 145 amino acid kisspeptins and it was originally identified as a human metastasis suppressor gene (suppresses melanomas and breast carcinomas without affecting tumorigenicity).[2]
Two hypothalamic nuclei, the arcuate nucleus and anteroventral periventricular nucleus (AVPV), are thought to contain the kisspeptin secreting neurons.
The anteroventral periventricular nucleus differs in males and females (sexually dimorphic). The arcuate nucleus (and medial preoptic area, MPOA) is linked into the olfactory system, through the vomeronasal organ, perhaps in relation to the influence of pheromones on sexual behavior and neuroendocrine function (in mice).[3]
Why Kisspeptin?
The original discovery of the peptide was made by scientists located in Hershey, PA, USA and named the gene "Kiss1" after the "Hershey chocolate kiss".
Gonadotropin Releasing Hormone (GnRH)
Neurons in the hypothalamic arcuate nucleus (and other nuclei) synthesise this hormone along with gonadotrophin associated peptide (GAP), which are both released and transported by hypophyseal portal capillaries to the anterior pituitary and bound by a membrane receptor.
GnRH increases during early puberty, followed by an increased pituitary responsiveness, then increasing sex steroid levels and then increased nocternal Luteinizing hormone (LH) secretion.
- Links: Endocrinology - GnRH and the control of gonadotrophin synthesis and secretion | Endocrinology - Synthesis of GnRH and its actions on pituitary gonadotrophs |
Female Postnatal Ovary Growth
Human ovary postnatal volume growth[4]
Animal Puberty
| Phase | Rat | Dog (beagle) | Primate (monkey) |
| Neonatal | Birth to postnatal Day 7 | Birth–3 weeks | Birth to 3–4 months |
| Infantile | Postnatal Days 8–21 | 3–5 weeks | Up to 29 months |
| Juvenile/prepubertal | Postnatal Days 22–37 | 5 weeks–6 months | Up to 43 months |
| Pubertal | Postnatal Days 37–38 | 6–8 months | 27–30 months |
Reading
Most embryology textbooks (by definition) do not cover postnatal developmenty in any detail. The links below are to useful scientific external online resources.
- PHYSICAL DEVELOPMENT, GROWTH, MATURATION, AND AGEING
- Patterns of Human Growth (PDF document)
- Causes and Mechanisms of Linear Growth Retardation
The links below are to general public external text resources (this listing is for information purposes only and is not intended as an endorsement of a commercial product).
- Ready, Set, Grow!: A What's Happening to My Body? Book for Younger Girls, by Lynda Madaras and Linda Davick
- What's Happening to My Body? Book for Boys: The New Growing-Up Guide for Parents and Sons, Third Edition by Lynda Madaras, Area Madaras, Dane Saavedra, and Simon Sullivan
- Sex, Puberty, and All That Stuff: A Guide to Growing Up, by Jacqui Bailey and Jan McCafferty
References
Reviews
<pubmed>17012487</pubmed> <pubmed>11397824</pubmed> <pubmed>16373418</pubmed>
Articles
<pubmed>16793957</pubmed>
Search Pubmed
April 2010
- puberty development - All (9053) Review (1407) Free Full Text (1747)
- puberty - All (26880) Review (3582) Free Full Text (4312)
- early puberty - All (4190) Review (676) Free Full Text (821)
Search Pubmed Now: puberty development | puberty | early puberty |
External Links
Australian
HealthInsite Puberty
Child and Youth Health (SA) - Puberty
American
National Institute of Child Health and Human Development Puberty | Precocious Puberty
American Academy of Family Physicians Puberty: What to Expect When Your Child Goes through Puberty
Nemours Foundation Precocious Puberty | Delayed Puberty |
Glossary Links
- Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link
Cite this page: Hill, M.A. (2024, April 26) Embryology Puberty Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Puberty_Development
- © Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G
