HSV1/2 Genital Infection in Mice Cause Reversible Delayed Gastrointestinal Transit: A Model for Enteric Myopathy

Area of Science:

• Virology
• Gastroenterology
• Urology

Background:

• Genital herpes simplex virus 1 (HSV1) infection in mice was reported to cause pelvic organ obstruction.
• The previous study suggested toxic megacolon as the cause of mortality in a subset of infected mice.
• Toxic megacolon is a severe condition involving colon dilation and toxemia.

Purpose of the Study:

• To investigate the effects of HSV1 genital infection on pelvic organ function in mice.
• To determine if HSV1 infection impairs autonomic neurotransmission and smooth muscle relaxation in pelvic organs.
• To clarify the cause of mortality in HSV1-infected mice.

Main Methods:

• The study critically reviewed the findings of Khoury-Hanold et al. regarding HSV1 infection in mice.
• Analysis focused on the reported gastrointestinal obstruction and its potential misclassification as toxic megacolon.
• Proposed further investigation using muscle strip recordings to assess pelvic organ dysfunction.

Main Results:

• The observed gastrointestinal obstruction in HSV1-infected mice was mild, resembling constipation, and reversible with polyethylene glycol.
• The colon dilation was minimal, not indicative of toxic megacolon.
• HSV1 infection appeared to affect postjunctional smooth muscle relaxation mechanisms, impacting nitrergic neurotransmission and transit.
• Mortality might be linked to bladder outlet obstruction and subsequent renal complications, rather than HSV1 encephalitis or toxic megacolon.

Conclusions:

• HSV1 genital infection causes pelvic organ dysfunction, characterized by impaired smooth muscle relaxation and delayed gastrointestinal transit.
• The condition observed is functionally closer to constipation than toxic megacolon.
• Bladder outlet obstruction is a potential cause of mortality in these cases.
• Further research involving direct physiological measurements is needed to confirm these findings.