Growth Hormone Structure and Function

Study Notes

Growth Hormone (GH) Structure and Characteristics

Growth hormone (GH) is a peptide hormone composed of 191 amino acids.
Its molecular weight is approximately 22 kDa.
GH shares a similar structure with prolactin and chorionic somatomammotropin (a placental hormone).
Two isoforms of GH exist, created through alternative splicing.
Most GH isoforms include all 5 exons, translating to a 191 amino acid protein with a 22 kDa molecular weight.
A smaller portion (10-15%) are generated from smaller mRNA molecules, missing part of exon III.

GH Production and Release

GH is produced by somatotrophs within the anterior pituitary gland.
GH release occurs in pulsatile bursts throughout the day, with a peak release mostly during the night, often associated with deep sleep.
GH release is also increased during exercise and trauma.

Factors Influencing GH Release

Nutritional status influences GH release.
Metabolic conditions affect GH release.
Age-related sex steroids impact GH release.
Adrenal glucocorticoids affect GH release.
Thyroid hormones influence GH release.
Renal function plays a role in GH release regulation.
Hepatic function affects GH release.

GH Circulation

Normal circulating levels of GH are not explicitly detailed.
Information on GH blood levels and binding is not fully included in the provided text.

Description

Explore the fascinating structure and characteristics of growth hormone (GH), a peptide hormone vital for growth and metabolism. This quiz delves into GH production, release patterns, and the various factors influencing its levels in the body. Perfect for students interested in human physiology and endocrinology.