Halothane induced significantly longer polymorphic ventricular tachycardias in female mice hearts compared to male hearts (378+/-144 seconds vs 27+/-10 seconds, P<0.05).
Does sex influence halothane-induced polymorphic ventricular tachycardia in mice hearts?
Female mice hearts exhibit significantly longer durations of halothane-induced polymorphic ventricular tachycardia compared to male hearts, potentially linked to differences in KCNE1 expression.
Absolute Event Rate: 378% vs 27%
p-value: p=<0.05
BACKGROUND: Molecularly engineered mice are extensively used as models of cardiovascular diseases, yet little is known about sex differences in the electrophysiology of mouse hearts. METHODS AND RESULTS: This study investigated the influence of sex on drug-induced polymorphic ventricular tachycardia (PVT) in Langendorff-perfused male and female mice hearts (n=54) by injecting a bolus of halothane (1.75 mmol/L) in the perfusate while recording ECGs or optical action potentials (APs). There were no statistically significant differences between male and female hearts (n=54) with respect to mean RR (193+/-5 ms), PR (47+/-1 ms), QT intervals (101+/-3 ms), optical AP durations (APD(75)=23.11+/-4.2 ms), dispersion of refractory periods, and conduction velocities (n=5 male and 5 female). Halothane induced PVTs lasting a mean duration of 90 seconds; in female hearts, 55% of PVTs lasted longer than the median, whereas in male hearts 17% exceeded the mean (P<0.05). The total duration of PVTs exposed a marked sex difference, 378+/-144 seconds in female versus 27+/-10 seconds in male hearts (P<0.05). In optically mapped male hearts, halothane reduced APD(75) (17.61+/-1.6 ms) and then elicited VTs (n=6 of 6), but in female hearts, halothane elicited PVTs (n=1 of 6) or arrested the hearts (n=5 of 6). Except for KCNE1, Northern blots (KCNQ1, MERG, Kv1.5, connexins 40 and 43, TREK1, and TASK1) did not detect sex differences. CONCLUSIONS: This mouse model reveals sex difference in response to a pharmacological challenge yet does not display sex differences in standard electrophysiological parameters. Differences in KCNE1 may contribute to sex differences uncovered by halothane.
Drici et al. (Tue,) conducted a other in Drug-induced polymorphic ventricular tachycardia (n=54). Halothane vs. Male mice hearts was evaluated on Total duration of polymorphic ventricular tachycardias (PVTs) (p=<0.05). Halothane induced significantly longer polymorphic ventricular tachycardias in female mice hearts compared to male hearts (378+/-144 seconds vs 27+/-10 seconds, P<0.05).