PreBotzinger complex neurokinin-1 receptor-expressing neurons mediate opioid-induced respiratory depression.

The analgesic properties of the opium poppy Papever somniferum were first mentioned by Hippocrates around 400 BC, and opioid analgesics remain the mainstay of pain management today. These drugs can cause the serious side-effect of respiratory depression that can be lethal with overdose, however the critical brain sites and neurochemical identity of the neurons mediating this depression are unknown. By locally manipulating neurotransmission in the adult rat, we identify the critical site of the medulla, the preBötzinger complex, that mediates opioid-induced respiratory depression in vivo.

Calcium and Vitamin D increase mRNA levels for the growth control hIK1 channel in human epidermal keratinocytes but functional channels are not observed.

Background: Intermediate-conductance, calcium-activated potassium channels (IKs) modulate proliferation and differentiation in mesodermal cells by enhancing calcium influx, and they contribute to the physiology of fluid movement in certain epithelia. Previous reports suggest that IK channels stimulate proliferative growth in a keratinocyte cell line; however, because these channels indirectly promote calcium influx, a critically unique component of the keratinocyte differentiation program, an alternative hypothesis is that they would be anti-proliferative and pro-differentiating. This study addresses these hypotheses.

Basal lamina of ovarian follicle regulates an inward Cl(-) current in differentiated granulosa cells.

Patch-clamp experiments were conducted to study the effects of basal lamina (basement membrane) of preovulatory chicken ovarian follicle on membrane currents in differentiated chicken granulosa cells in a homologous system. The membrane capacitance (measure of total membrane area) was smaller in cells cultured on intact basal lamina than that of control cells. The granulosa cells expressed outward and two inward currents.

Effect of basal lamina of ovarian follicle on T- and L-type Ca(2+) currents in differentiated granulosa cells.

Patch clamp experiments were conducted to study the effects of basal lamina (basement membrane) of chicken ovarian follicle on membrane Ca(2+) currents in differentiated chicken granulosa cells in a homologous system. The whole cell patch clamp technique was used to simultaneously monitor membrane capacitance (an indirect measure of total cell surface area) and currents flowing through voltage-dependent Ca(2+) channels (using Ba(2+) as the charge carrier). Membrane capacitance was smaller in cells incubated on intact basal lamina than in control cells (incubated on tissue culture-treated plastic substratum).