+- USMLE Forum - Largest USMLE Community (https://www.usmleforum.com)
+-- Forum: USMLE Forum (https://www.usmleforum.com/forumdisplay.php?fid=1)
+--- Forum: Step 1 (https://www.usmleforum.com/forumdisplay.php?fid=2)
+--- Thread: @sarahmle - cardio69 (/showthread.php?tid=788021)
@sarahmle - cardio69 - ArchivalUser - 09-09-2014
A neurophysiologist research on the functional properties of various R/eceptor subtypes, using whole cell voltage clamp recordings made from coronal brain slices. At a holding potential of -70mV, bath application of R agonists for four different R types consistently elicited either excitatory post synaptic currents or inhibitory past synaptic currents. During the study of one R, however, agonist application failed to elicit a post synaptic response at – 70 mV but did elicit a reliable response at a holding potential of 0 mV. This R is most likely which of the following? [ http://i.imgur.com/6hDHdim.png?1]
a)GABA/a
b)Kainate
c)N-methyl-d-aspartate
d)Nicotinic Ach
e)5-HT3
0 - ArchivalUser - 09-09-2014
http://cro.pm/oMlwC
0 - ArchivalUser - 09-09-2014
Sorry im late... is it D? Desensitization.
pls explain
0 - ArchivalUser - 09-09-2014
C. thanks cardio. Nice one.
0 - ArchivalUser - 09-10-2014
@sallu... pls explain
0 - ArchivalUser - 09-10-2014
@sarahmle the reason post the q for u want u to ans http://www.usmleforum.com/showthread.php?tid=787936 ASSO ovarian Teratoma
*NMDA R type of glutamate R : Ligand gated & Voltage. Both an AGONIST & neuronal DEpolarization to be Activated.
Kainate R/glutamate R, 5-HT3 R , and nicotinic Ach R LIGAND GATED Na channels. GABA L-G Cl channel.
*is an ioon channel that allow the passage Ca & Na OPEN. @ resting membrane potentioal the channel plugged by Mg. DEPolariaztion ( & agonist activation ) cz the Mg to dislodge, perm R to functional.
@ HI, sall welcome! You are senior & ALL my Qs here would be 72sec base timed for you from time the q posted.
0 - ArchivalUser - 09-10-2014
thanq cardio. nw it makes sense
0 - ArchivalUser - 09-10-2014
Welcome
make sure u know it well. Q Kaplan
0 - ArchivalUser - 09-10-2014
@sarah can u ans the following ******nb1 ____________ATTN_____________
A pharmaceutical company has developed a drug that prevents egress of Mg from the NMDA R. What is the most likely effect of this drug in a patient with an acute stroke?
a)Decreased risk for seizures due to hypomagnesemia
b)Prevention of Ca entry into the neuron & reduction of excitation-mediated cell death
c)Hyperpolarization of membrane & conduction block
d)Facilitation of Ca entry into the neuron & enhancement of excitation-mediated cell death
e)Rapid depolarization of membrane with lowering of the seizure threshold
0 - ArchivalUser - 09-10-2014
Hello cardio. All ur qs seem tough 2 me .
I will go with BB. Like u said b4, nmda allow ca entry and that it is plugged by Mg. So if ur makin a drug which is egressin/removing mg frm nmda receptor. Then it shudnt allow ca flow.
this physio is very tough 2 me. Pls explain if nay blunder
n thanq so much fr all ur qs cardio.