Sex differences in the acetylcholine receptor kinetics of postnatal and denervated rat muscle.
Single-channel recording from visualised endplates in freshly dissociated muscles from postnatal and denervated rat muscle revealed the presence of a low conductance, fetal type of acetylcholine receptor. Kinetic analysis showed a main component in the burst durations with a mean of 10.8 +/- 2.7 ms (n = 29). Receptors from female rats had an additional 27.3 +/- 5.5 ms (n = 5) kinetic component which was found in one-third of the 15 female endplates. Recordings from male and female denervated muscles gave more homogeneous kinetics with single time constants of 7.2 +/- 1.3 and 7.4 +/- 1.3 ms, respectively. It is concluded that the acetylcholine receptor channels present during early development are different from those of denervated muscle.
Department of Physiology and Biophysics, Dalhousie University School of Medicine, 3R1 Tupper Medical Building, Halifax, Nova Scotia, Canada B3H 4H7. avillarr@is.dal.ca
A
A
Villarroel
D000818:Animals; D000831:Animals, Newborn; D005260:Female; D007700:Kinetics; D008297:Male; D009045:Motor Endplate / Q000502:physiology*; D009121:Muscle Denervation; D018482:Muscle, Skeletal / Q000294:innervation* / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D011950:Receptors, Cholinergic / Q000502:physiology*; D012727:Sex Characteristics
D011950:Receptors, Cholinergic