Estrogenic impregnation alters pain expression: analysis through functional neuropeptidomics in a surgical rat model of osteoarthritis

Face and Predictive Validity of MI-RAT (Montreal Induction of Rat Arthritis Testing), a Surgical Model of Osteoarthritis Pain in Rodents Combined with Calibrated Exercise

“…For example, in a recent study of the contribution of CGRP in OA mice stifles, the authors did not mention the sex of the animals used [76]. In addition, our process of validating the MI-RAT model confirmed that sterilized female rats favorably increased data homogeneity by reducing variability in pain outcome measures because estrogen supplementation interfered with central sensitization in OVX rats [27].…”

“…pharmacologic analgesic treatment. To address these objectives, a prospective, randomized, blinded, and controlled study was conducted in a prevalidated Sprague-Dawley rat model of surgically induced OA [26,27]. The MI-RAT (Montreal Induction of Rat Arthritis Testing) model, which combines cranial cruciate ligament transection (CCLT) and destabilization of the medial meniscus (DMM), thus allowing for the progressive development of chronic OA pain based on joint instability and forced mobilization, was compared with sedentary conditions, as previously tested [26].…”

“…After surgical preparation on D0, right stifle instability was performed in the rats following a CCLT-DMM procedure, as previously described [26,27]. Before surgery (40 min before general anesthesia was administered), an intramuscular injection of buprenorphine (Buprenorphine SR ® , Chiron Compounding Pharmacy Inc., Guelph, ON, Canada) was administered at a 1.0 mg/kg dose.…”

“…The specific objectives were: (i) to quantify the analgesic (tactile sensory sensitivity and targeted spinal neuropeptides) and structural (stifle histology) effects induced by forced exercise alone or a multimodal pharmacologic analgesic treatment after OA induction; (ii) to compare the expression of neurotransmitters affected by exercise or multimodal pharmacologic analgesia; and (iii) to test the interaction between exercise and multimodal pharmacologic analgesic treatment. To address these objectives, a prospective, randomized, blinded, and controlled study was conducted in a prevalidated Sprague-Dawley rat model of surgically induced OA [26,27]. The MI-RAT (Montreal Induction of Rat Arthritis Testing) model, which combines cranial cruciate ligament transection (CCLT) and destabilization of the medial meniscus (DMM), thus allowing for the progressive development of chronic OA pain based on joint instability and forced mobilization, was compared with sedentary conditions, as previously tested [26].…”

Immunohistochemical expression of estrogen receptor alpha in the maxillary sinus, pulp, and periodontal ligament of adjacent teeth in late pregnancy in rats

“…Scale bar:100 µm (a-g) ◂ Ribeiro-Dasilva et al [49] declared that estrogen receptors are present in the dorsal root ganglion and trigeminal nerve nucleus, therefore, the oscillations of estrogen level may change the opioid systems function, boosting perception of pain. Keita-Alassane et al, reported that woman's pain threshold may be influenced by instability of estrogen levels [50]. Fortunately, dental pain does not occur in all pregnant women.…”