The final Flashcards
what are the effects of the active form of Vit D. 1,25-dihydroxycholecalciferol?
- increase calcium and phosphate absorption in the kidneys, intestine and bones. Increasing extracellular fluid concentration and forming a feedback regulation.
What domains are present on the Vit D receptors?
hormone binding and DNA binding domains
What is required for Vitamin D to induce DNA transcription?
must form a complex with retinoid-X receptor in order for both to bind to DNA and induce trasncription. used as a control check point.
Can vitamin cause activation of inhibition of DNA transcription when bound with the retinoid -X receptor?
Can induce activation and inhibition
Where are the majority of vitamin D receptors located?
- most cells of the body in the nuclei of the cells
What is calbindin?
calcium binding protein which is expressed in intestinal cells to increase calsium reabsorption
Where does calbindin operate?
brush border of epithelial cells to move Calcium into the cell cytoplasm
How does absorbed calcium migrate through the cell?
facilitated diffusion through the basolateral membrane
WHat are characteristics of postganglionic sympathetic fibers?
- pass through the gray rami
- Type C
- 8% of fibers in the average nerve
- control blood vessel, piloerection, sweat glands
Waht are splanchnic nerves?
preganglionic fibers and visceral sensory fibers that supply the abdominal viscera when synapsed in the prevertebral ganglia.
Where do the greater, lesser and least splanchnic nerves arise from?
- greater: T5-T9 synapse in celiac ganglion
- lesser: T10-T11 synapse in superior mesenteric ganglion
- least: T12 synapse in aorticorenal ganglion
How many parasympathetic fibers are in the vagus nerve?
75%
75% of all parasympathetic nerves are located where?
in the vagus nerve
What are features of postganglionic parasympathetic fibers?
- they locate in the wall of an organ
2. they use Ach as neurotransmitter
What is the funciton of the oculomotor nerve?
- provides muscular innervation to 4 of the 6 extrinsic eye muscle and levator palpebra superioris.
What are the parasympathetic pathways of the ocuomotor nerve?
- preganglionic: from edinger-westphal nucleus to the ciliary ganglion
- postganglion: from ciliary ganglion to the sphincter pupillae muscle
What is the function of teh facial nerve?
- facial expression
2. sensation from anterior 2/3 of tongue.
What are the pathways of the parasympathetics of the facial nerve?
- pre: from superior salivatory/lacrimal nuclei to submandibular/sublingual ganglia
- post: to the lacrimal gland, subandibular, sublingual, and mucous gland of mouth/nose
What are the function of the glossopharyngeal nerve?
- carry general sensation and sensation of taste from the posterior 1/3 of teh tongue.
What are the parasympathetic pathways of teh glossopharyngeal nerve?
- pre: from the inferior salivatory nucleus to the otic ganglion
- post: from otic ganglion to parotid gland