bone Calcium homeostasis Blood Ca++ small intestine kidney

Calcium cycling in bone tissue Bone formation –Osteoblasts Synthesize a collagen matrix that holds Calcium Phospate in crystallized form Once surrounded by bone, become osteocyte Bone resorption –Osteoclasts Change local pH, causing Ca++ and phosphate to dissolve from crystals into extracellular fluids

1,25 Vitamin D3

Mammalian Pancreas Gall bladder duodenum liver Bile Duct Pancreas Pancreatic duct

Endocrine Pancreas Islets of Langerhans Exocrine cells    capillaries

Islet Transplantation Inside the patient Separate islets from exocrine pancreas Encapsulate islets (immune protection) Inject into abdomen

Alarm Phase: Catecholamine Release: sympathoadrenal system Adrenal Gland Neuron epinephrine

hypothalamus pituitary adrenals Glucocorticoids (cortisol, corticosterone) ACTH CRH Central Nervous System VP  -endorphins Prolactin

The stress response

Pre-storm (n=3) Calm (n=8) Time after capture (min) Corticosterone, ng/ml Storm? Storms and CORT in diving Petrels

glucose mobilization Breakdown of protein to make glucose Inhibit immune system Decreased parental care Decrease reproduction Energy depletion Muscle wasting Increase parasite load, can’t fight disease, infection Loss of young Total loss of fitness for the season Acute Responses to StressChronic Stimulation

Corticosterone and Body Condition fence lizard

PESASESAWESAREPH Males Females Magnitude ofCorticosterone Increase, ng/ml Pectoral Sandpiper Semipalmated Sandpiper Red Phalarope F M + F MParental care? :

Abert's Towhee summer winter Inca Dove Time after capture (mintues) CORT (ng/ml) winter summer summer winter Cactus Wren Black-throated sparrow BENIGN BREEDING ENVIRONMENT HARSH BREEDING ENVIRONMENT

EIEI E ENERGY TIME E I = E E = E O = Energy Model E G =