BIOL1040 Lecture Notes - Lecture 6: Diabetes Mellitus Type 2, Renin, Mammary Gland
Module 6 - endocrinology
Lecture 1
principles of endocrine function
3 stages of cell signalling:
Reception
Transduction
Response
Cell to cell communication: local vs. long-distance signalling
Local:
oParacrine signalling: secreting cell acts on nearby target by secreting molecules of a
local regulator (a growth factor, for example)
oSynaptic signalling: nerve cell released neurotransmitter molecules into a synapse,
simulating the target cell such as a muscle or nerve cell
Long-distance:
oEndocrine (hormonal) signalling: specialised endocrine cells secrete hormones into
body fluids, often blood. Hormones reach virtually all body cells, but are bound only by
some cells
Types of chemical signalling
1. Endocrine signalling: secreted molecules (hormones) diffuse into the blood stream,
circulate, and trigger responses in target cells anywhere in the body
2. Synaptic signalling: secreted molecules (neurotransmitters) diffuse across a synapse,
triggering a response in cells of the targeted tissue
3. Neuroendocrine signalling: secreted molecules (neurohormones) diffuse into the
blood stream, circulate, and trigger responses in target cells anywhere in the body
4. Paracrine signalling: secreted molecules (local regulators) diffuse locally through the
ECF, triggering a response
5. Autocrine signalling: secreted molecules (local regulators) diffuse locally, triggering a
response in the cell which secreted them
Regulation and Homeostasis
Animals manage their internal environment by
oRegulating their internal environment despite external fluctuation
oOr… allowing internal condition to conform to the external environment
Organisms use homeostasis to maintain a 'steady state' or internal balance
oIndependent of conditions in the external environment
How do hormones work? - endocrine function in animals
One of the modes of long distance 'communication' in animals
Endocrine cells in various organs and tissues
oRelease chemicals ('hormones') that are distributed into the bloodstream
Hormones act on target cells as 'messengers'
oTell the cells how to behave and act
Receptors - 'specificity'
Types of hormones - chemistry
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Cell to cell communication: local vs. long-distance signalling. Paracrine signalling: secreting cell acts on nearby target by secreting molecules of a local regulator (a growth factor, for example) o. Synaptic signalling: nerve cell released neurotransmitter molecules into a synapse, simulating the target cell such as a muscle or nerve cell. Endocrine (hormonal) signalling: specialised endocrine cells secrete hormones into body fluids, often blood. Hormones reach virtually all body cells, but are bound only by some cells. Endocrine signalling: secreted molecules (hormones) diffuse into the blood stream, Synaptic signalling: secreted molecules (neurotransmitters) diffuse across a synapse, 1. circulate, and trigger responses in target cells anywhere in the body. 2. triggering a response in cells of the targeted tissue. 3. blood stream, circulate, and trigger responses in target cells anywhere in the body. 5. response in the cell which secreted them. Neuroendocrine signalling: secreted molecules (neurohormones) diffuse into the. Paracrine signalling: secreted molecules (local regulators) diffuse locally through the.
