Recent work has implicated stimulatory kisspeptin neurons in the arcuate nucleus (ARC) as important for seasonal changes in reproductive function in sheep, but earlier studies support a role for inhibitory A15 dopaminergic (DA) neurons in the suppression of GnRH (and LH) pulse frequency in the nonbreeding (anestrous) season. Because A15 neurons project to the ARC, we performed three experiments to test the hypothesis that A15 neurons act via ARC kisspeptin neurons to inhibit LH in anestrus: 1) we used dual immunocytochemistry to determine whether these ARC neurons contain D2 dopamine receptor (D2-R), the receptor responsible for inhibition of LH in anestrus; 2) we tested the ability of local administration of sulpiride, a D2-R antagonist, into the ARC to increase LH secretion in anestrus; and 3) we determined whether an antagonist to the kisspeptin receptor could block the increase in LH secretion induced by sulpiride in anestrus. In experiment 1, 40% of this ARC neuronal subpopulation contained D2-R in breeding season ewes, but this increased to approximately 80% in anestrus. In experiment 2, local microinjection of the two highest doses (10 and 50 nmol) of sulpiride into the ARC significantly increased LH pulse frequency to levels 3 times that seen with vehicle injections. Finally, intracerebroventricular infusion of a kisspeptin receptor antagonist completely blocked the increase in LH pulse frequency induced by systemic administration of sulpiride to anestrous ewes. These results support the hypothesis that DA acts to inhibit GnRH (and LH) secretion in anestrus by suppressing the activity of ARC kisspeptin neurons.

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BACKGROUND AND OBJECTIVE: Pediatric interfacility transport teams facilitate access to subspecialty care, and physicians often guide management remotely as transport medical control (TMC). Pediatric subspecialty fellows frequently perform TMC duties, but tools assessing competency are lacking. Our objective was to develop content validity for the items required to assess pediatric subspecialty fellows’ TMC skills. METHODS: We conducted a modified Delphi process among transport and fellow education experts in pediatric critical care medicine, pediatric emergency medicine, neonatal-perinatal medicine, and pediatric hospital medicine. The study team generated an initial list of items on the basis of a literature review and personal experience. A modified Delphi panel of transport experts was recruited to participate in 3 rounds of anonymous, online voting on the importance of the items using a 3-point Likert scale (marginal, important, essential). We defined consensus for inclusion as ≥80% agreement that an item was important/essential and consensus for exclusion as ≥80% agreement that an item was marginal. RESULTS: The study team of 20 faculty drafted an initial list of items. Ten additional experts in each subspecialty served on the modified Delphi panel. Thirty-six items met the criteria for inclusion, with widespread agreement across subspecialties. Only 1 item, “discussed bed availability,” met the criteria for inclusion among some subspecialties but not others. The study team consolidated the final list into 26 items for ease of use. CONCLUSIONS: Through a consensus-based process among transport experts, we generated content validity for the items required to assess pediatric subspecialty fellows’ TMC skills.

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