BIOD27H3 Lecture Notes - Menopause, Prolactin, Exocytosis
11 Aug 2010
School
Department
Course
Professor
BGYB30H3 Lecture 21 Notes
-normal growth requires
x Sex hormones
x Insulin and insulin growth factors
x Growth hormones
x thyroid hormone
x diet (nutrients such as calcium)
x genetics
-cortisol has catabolic effects on growth by increased calcium in the blood
-peak growth occurs during teenage years
-nutrients, circadian rhythms and other hormones stimulate growth hormone
-growth hormone that binds to binding protein in the blood increases its half life in the blood to
prevent excretion in urine
-growth rate is determined by amount of GH binding protein in the blood
-growth hormone stimulates release of insulin like growth factors from the liver, which
negatively feedback on GH
-IGF and GH cause
x bone and soft tissue growth
x increased protein synthesis
x cartilage growth
x breakdown of glycogen and triglycerides
-dwarfism is less common now due to medications and is caused by inhibiting of bone growth
-giantism is caused by excess bone growth
-acromegaly is caused by excess soft tissue and cartilage growth in adults and is progressive
-growth hormone causes both hyperplasia (cell division increase) and hypertrophy (increased
cell size)
-bone growth requires sex hormones, IGFs, GH, TH and calcium
-calcium is stored as a calcium phosphate crystal
-the bone is dynamic in that it is constantly being formed and broken down even after bone
lengthening ceases
-bone contains compact bone layer for strength and spongy trabecular bone layer that is less
solid
-osteoblasts are bone forming cells that produce enzymes and osteoids
-osteoclasts dissolve bone to release calcium by releasing acid and enzymes
-epiphysis is the end of the bone while the shaft of the bone is the diaphysis
-epiphysial plate is where bone growth occurs because osteoblasts are found there
-diaphysis is where bone diameter increases
-chondrocytes are found under the compact bone of the epiphysis and osteoblasts are found
under chondrocytes
-chondrocytes divide to add length to the bone as well as cartilage
-osteoblasts lay down bone on top of the cartilage to replace dead chondrocytes
-following puberty, sex hormones inactive the epiphysial plate to cause bone growth to stop
www.notesolution.com
Document Summary
Cortisol has catabolic effects on growth by increased calcium in the blood. Nutrients, circadian rhythms and other hormones stimulate growth hormone. Growth hormone that binds to binding protein in the blood increases its half life in the blood to prevent excretion in urine. Growth rate is determined by amount of gh binding protein in the blood. Growth hormone stimulates release of insulin like growth factors from the liver, which negatively feedback on gh. Dwarfism is less common now due to medications and is caused by inhibiting of bone growth. Acromegaly is caused by excess soft tissue and cartilage growth in adults and is progressive. Growth hormone causes both hyperplasia (cell division increase) and hypertrophy (increased cell size) Bone growth requires sex hormones, igfs, gh, th and calcium. Calcium is stored as a calcium phosphate crystal. The bone is dynamic in that it is constantly being formed and broken down even after bone lengthening ceases.
