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Ca2+ entry into nigrostriatal dopamine (DA) neurons and axons via L‐type voltage‐gated Ca2+ channels (LTCCs) contributes, respectively, to pacemaker activity and DA release and has long been thought to contribute to vulnerability to degeneration in Parkinson's disease. LTCC function is greater in DA axons and neurons from substantia nigra pars compacta than from ventral tegmental area, but this is not explained by channel expression level. We tested the hypothesis that LTCC control of DA release is governed rather by local mechanisms, focussing on candidate biological factors known to operate differently between types of DA neurons and/or be associated with their differing vulnerability to parkinsonism, including biological sex, α‐synuclein, DA transporters (DATs) and calbindin‐D28k (Calb1). We detected evoked DA release ex vivo in mouse striatal slices using fast‐scan cyclic voltammetry and assessed LTCC support of DA release by detecting the inhibition of DA release by the LTCC inhibitors isradipine or CP8. Using genetic knockouts or pharmacological manipulations, we identified that striatal LTCC support of DA release depended on multiple intersecting factors, in a regionally and sexually divergent manner. LTCC function was promoted by factors associated with Parkinsonian risk, including male sex, α‐synuclein, DAT and a dorsolateral co‐ordinate, but limited by factors associated with protection, that is, female sex, glucocerebrosidase activity, Calb1 and ventromedial co‐ordinate. Together, these data show that LTCC function in DA axons and isradipine effect are locally governed and suggest they vary in a manner that in turn might impact on, or reflect, the cellular stress that leads to parkinsonian degeneration. [ABSTRACT FROM AUTHOR]

Objective: To study the incidence of elective cesarean deliveries at term and to correlate their neonatal outcomes at different gestational ages (37-40). Methods: Outcomes including the rate of NICU admissions, usage of ventilator/CPAP, and other morbidities were analysed and compared with the gestational age during the study period from January 2012 to April 2013. Results: The incidences of elective deliveries at 37, 38, 39, and 40 weeks of gestation were 10.6, 29.7, 28, and 31.5 %, respectively. NICU admissions-RR 3.94 (95 % CI 1.92-8.09), respiratory distress-RR 5.255 (95 % CI 1.9-14.4), ventilatory usage, and hospitalization stay ( P value < 0.05) were higher in neonates born at 37 versus 39 weeks (least morbidity group). Conclusion: Despite recommendations, more than one-third of term babies are delivered electively at <39 weeks. The fivefold augmented respiratory morbidity and fourfold increased NICU admissions in early term neonates, and the least morbidity in neonates delivered at 39 weeks emphasize the importance of restricting the non-emergent/elective deliveries to 39 weeks of gestation. [ABSTRACT FROM AUTHOR]