Sex- and afferent-specific differences in histamine receptor expression in vagal afferents of XXXX : A potential mechanism for sexual dimorphism in prevalence and severity of asthma.

@entity1 @entity35090 @entity35089 @entity73217 @entity35
The incidence of asthma is more common in @entity1 than in @entity1 during the childhood, and more common in premenopausal female than age-matched males. Our previous study demonstrated a gender difference in histamine-mediated neuroexcitability in nodose ganglia neurons (NGNs), highlighting a possibility of histamine-mediated gender difference in asthma via visceral afferent function. In the present study, we aimed to explore the gender difference in expression profiles of histamine receptors (HRs) in nodose ganglia (NG) and individual identified NGNs to provide deeper insights into the mechanisms involved in sexual dimorphism of asthma. Western-blot and SYBR green RT-PCR showed that @entity73217 and @entity35090 were highly expressed in NG of females compared with males and downregulated in ovariectomized females. @entity35089 was equally expressed in NG of both sexes and not altered by ovariectomy. Furthermore, this highly expressive @entity73217 and @entity35090 were distributed in both myelinated and unmyelinated NGNs isolated from adult female @entity35 by immunofluorescence and single-cell RT-PCR. @entity35090 widely distributed in all tested neuron subtypes and its expression did not show significant difference among neuron subtypes. @entity73217 was widely and highly expressed in low-threshold and sex-specific subpopulation of myelinated Ah-types compared with myelinated A- and unmyelinated C-type NGNs. Unexpectedly, weak expression of @entity35089 was detected in both myelinated and unmyelinated NGNs by immunofluorescence, which was further confirmed by single-cell RT-PCR. Our results suggest that the sexual dimorphism in the expression of @entity73217 and @entity35090 in vagal afferents very likely contributes, at least partially, to the gender difference in prevalence and severity of asthma.
