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Unformatted text preview: e cell take hours to take effect… takes time to make new protein make Nongenomic effects: steroid hormones
More • More recently, it has been discovered that steroid hormones can have more rapid effects by acting at a different class of receptors on the cell membrane membrane Estrogen • Estrogen is a steroid hormone that has these ‘non-genomic’ effects (in addition to its classic genomic effects) Comparisons With Neural Signaling • Similarities... neurons and endocrine cells both produce, store, and release chemical messages neurons and endocrine cells are directed to release chemical messages by other cells neurotransmitters and hormones act on receptor proteins; some using second messengers • Differences... neural is direct, hormones are diffuse Many neural signals are fast (ms), hormonal messages are slow (sec to min) Major Endocrine Glands Pituitary Gland
Base • Base of brain below hypothalamus… the pituitary gland is a major endocrine gland major Consists • Consists of two distinct components, the anterior pituitary and the posterior pituitary (completely separate in function) separate Pituitary Gland
Connected • Connected to hypothalamus via pituitary stalk (aka infundibulum) infundibulum) Oxytocin (OT) and Oxytocin vasopressin (AVP) neurons in the hypothalamus project to the posterior pituitary to These neurons are called These hypothalamic neurosecretory cells extend all the way into posterior pituitary posterior Terminate on capillaries and Terminate action potentials release OT and AVP into blood stream and • • • Posterior Pituitary Gland Neurosecretory • Neurosecretory cells in
hypothalamus hypothalamus • Oxytocin (OT) stimulates uterine • Vasopressin (AVP) contractions triggers milk letdown facilitates social bonds (released during orgasm) acts on kidney to reduce urine output (water conservation) increases blood pressure Hormones and Brain
Brain • Brain also has receptors for hormones (neuropeptide transmitters) transmitters) OT • OT and AVP also act within the brain to mediate learning and memory, aggression, and social bonding social Anter...
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This note was uploaded on 02/18/2011 for the course PSYCH 230 taught by Professor Unkown during the Winter '08 term at University of Michigan.
- Winter '08