TRPV1 Gate Open Prob. 12.4% Sub-threshold
Afferent Spike Rate 14 Hz Basal / Mild
Enteric Prostaglandin 1.2x Normal Peristalsis
Myometrial Contractility Low Tone Physiological Quiescence
REFLEX SEQUENCE:
Active 60 FPS
1
Stage 1: Lingual & Gastric Mucosal TRPV1 Activation Ingested capsaicin binds to intracellular vanilloid binding pockets on primary sensory nerve terminals (vagal & splanchnic afferents) across the lingual epithelium and gastric rugae.

TRPV1 Homotetramer Molecular Pocket Gating

The transient receptor potential vanilloid 1 (TRPV1) channel is a homotetramer where each subunit contributes transmembrane segments S1–S4 forming the vanilloid binding pocket (residues Y511, S512, T550) and S5–S6 forming the central cation-conducting pore.

EC50 Reference Values
Human TRPV1 EC50 0.71 μM
Rat TRPV1 EC50 0.29 μM
Hill Coefficient (nH) 1.84 (Cooperative)
Pore Ion Permeability

Selectivity ratio PCa:PNa ~ 9.6:1. Activation allows massive intracellular Ca2+ surge, triggering calcineurin dephosphorylation and receptor desensitization if exposure is sustained.

Pelvic Visceral Cross-Sensitization (The Neural Reflex Arc)

The primary physiological mechanism linking extreme dietary spice to uterine irritability is not direct transplacental or plasma capsaicin diffusion, but viscerovisceral cross-sensitization mediated by shared primary afferent projections into the lumbosacral spinal cord (L6–S2).

● 1. Colorectal / Rectal Mucosa