Lecture 8 Flashcards
In the polyphospho inositide system G protein exchanges
GDP for GTP and activates phospholipase C
Phospholipase C cleaves PIP2 into three molecules
Arachidonic acid, IP3, and Diaclyglcerol
IP3 gets broken down to
IP4
IP3 and IP4 promotes the release of
Calcium in different ways
In the PPI system ca in the cell favors the activation of
Guanylyl Cyclase, which convert GTP to cGMP
In the ppI system cGMP activates
Kinase G
Kinase G will activate
Some transcription factor which will lead to change in generic levels
IP3 goes to the —– and promote the release of —–
SER calicstome ….ca
IP4 opens……channels in the cell membrane
Ca
DAG activates
Protein kinase C by directing the protein to the cell’s membrane by trafficking protein. It is only activated when it is on the cells membrane
leptin receptor
it is pleiothropic, it can either activate other enzyme or it can activate or phosphorylate transcription factor directly. it also affect diet, BMI, and appetite control… it is produce by adipocytes
leptin receptor are directly linked to
the jak2 which autophosphorylate or trans phosphorylate when leptin is bind to the leptin receptor. then the JaK2 phosphorylate other protein.
receptor/ enzyme are in the ……. when it is not attached to it ligan
inactivated form
second messenger have 3 origins which are
it can be synthesized within the cell (cAMP or cGMP)
it can released within the cell by organelle(Ca from SER)
it can be imported from its external
environment ( ca though the ca channel)
second messengers
a sudden increase of a molecule in the cytoplasm after a substrate had bind to its receptor on the cell membrane or with in the cyctoplasm
divergent signaling pathway
one substrate that can affect two different receptor that hass different signaling cascades leading to two different responses
example divergent signaling pathway
salivary gland, the hormone can either bind to the beta or alpha cells of the gland. if it binds to alpha cells there will be a rise of ca in the cytoplasm which leads to secretion of fluid. if it binds to the beta cells there will be increase of the cAMp which cause release of more amylase
Convergent signaling pathway
one substate that can affect two different receptors signaling cascades leading to the same response.
example of convergent signaling pathway
Liver cells…. substrate can bind to different receptor, one which cause a rise in ca level in the cytoplasm and the other causes a rise cAMP in the the cytoplasm, which will lead to glycogenlysis
Neuro endocrine System
composed of specialized neuron that secrets Neuro hormone aka neuro-seretion. there are no synaptic connection between the neuron. the secretion goes into the blood stream in vesicles
neuro-secretion goes into the blood vessel mainly
capillaries and acts like a hormone
Neurohemal organ
is a collection of secretory neuron and its blood vessel, ADH, pituitary Gland (hypoPhysis ) and Hypothalamus found in the floor of the third ventricle
infundibulum
the stem that connects the pituitary gland to hypothalamus
the hypothalamus is located at
the base of the brain