Timothy J. Brennan

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In this study, we developed a rat model of incisional pain. A 1-cm longitudinal incision was made through skin, fascia and muscle of the plantar aspect of the hindpaw in halothane-anesthetized rats. Withdrawal responses were measured using von Frey filaments at different areas around the wound before surgery and for the next 6 days. A cumulative pain score(More)
Cation channels in the DEG/ENaC family are proposed to detect cutaneous stimuli in mammals. We localized one such channel, DRASIC, in several different specialized sensory nerve endings of skin, suggesting it might participate in mechanosensation and/or acid-evoked nociception. Disrupting the mouse DRASIC gene altered sensory transduction in specific and(More)
P2X3 and P2X2/3 receptors are highly localized on peripheral and central processes of sensory afferent nerves, and activation of these channels contributes to the pronociceptive effects of ATP. A-317491 is a novel non-nucleotide antagonist of P2X3 and P2X2/3 receptor activation. A-317491 potently blocked recombinant human and rat P2X3 and P2X2/3(More)
Acute postoperative pain remains a significant medical problem. Patients undergoing outpatient ambulatory surgery have clinically significant postoperative pain, even when administration of oral opioids and nonopioid adjuncts are optimized [1]. Regional analgesic techniques improve pain control, except their use is limited to a minority of all surgical(More)
BACKGROUND Guarding pain after rat plantar incision is similar to pain at rest in postoperative patients. Spontaneous activity (SA) in nociceptive pathways quite likely transmits such ongoing pain. This study examined the extent of tissue injury by incision on pain behaviors and nociceptor SA. METHODS Rat pain behaviors were measured after a sham(More)
Acutely, nerve growth factor (NGF) exerts profound effects on nociceptive transmission and produces pain and hyperalgesia. In the present study, we sought to determine the tissue levels and role of NGF after a plantar incision. A substantial increase in NGF protein expression occurred in skin 4-h, 1-day and 2-days and 5-days after incision comparing(More)
BACKGROUND & AIMS Visceral mechanoreceptors are critical for perceived sensations and autonomic reflex control of gastrointestinal function. However, the molecular mechanisms underlying visceral mechanosensation remain poorly defined. Degenerin/epithelial Na+ channel (DEG/ENaC) family ion channels are candidate mechanosensory molecules, and we hypothesized(More)
BACKGROUND AND OBJECTIVES Patients undergoing liver resection may have marginal preoperative liver function, extensive intraoperative blood loss, and perioperative hepatic dysfunction. We evaluated the prevalence and types of coagulopathic conditions that occur in patients with epidural catheters undergoing hepatic resection. METHODS A retrospective chart(More)
TrpV1, the receptor for capsaicin, contributes to nociception in animals but appears to be much more important for signaling increased behavioral sensitivity in the injured state. The current study examined the relationship between the marked reduction in heat hyperalgesia after incision in TrpV1 knockout (KO) mice and the activity of the nociceptors in(More)
Even though it is a costly, poorly understood problem, very little effort has been dedicated toward research on the mechanisms of acute postoperative pain. Presumably, if we learn more about the etiology of acute incisional pain and the sensory processes that intensify pain after surgery, new treatment methods can be advanced. Since the mid-1990s, our group(More)