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F Cankat Tulunay

Publications and source records attributed to F Cankat Tulunay.

6 recordsLinked to original sources

Airway smooth muscle relaxations induced by dipyrone.

BACKGROUND: Dipyrone differs from other nonsteroidal anti-inflammatory drugs with a distinctive spasmolytic effect; however, the mechanism of action is not clear yet. The possible mechanism behind this effect was investigated on airway smooth muscle tone in vitro. METHOD: The effect of dipyrone on inositol phosphate (IP) accumulation was evaluated on guinea pig trachea smooth muscle. Changes in intracellular free calcium levels and IP accumulation were evaluated in LTK8 cells. RESULTS: Dipyrone (0.01, 0.1, 1 mmol/l) had a relaxing effect on histamine (0.02 mmol/l)- and adenosine triphosphate- (ATP) (0.01 mol/l)-induced contractions, but not potassium chloride (KCl)-stimulated contractions. This relaxing effect was not observed with indomethacin. Indomethacin did not inhibit the relaxation response of dipyrone. In isolated tracheal smooth muscle, histamine- (0.02 mmol/l) and ATP (0.01 mmol/l)-induced IP accumulation was significantly inhibited by dipyrone (1 mmol/l). ATP (0.01 mmol/l)-induced IP accumulation was also significantly inhibited by dipyrone (0.01 mmol/l) in LTK8 cells. Dipyrone inhibited ATP-induced (0.01 and 0.1 mmol/l) intracellular calcium increase in LTK8 cells. CONCLUSION: Inhibition of the release of intracellular Ca(2+) may play a role in the smooth muscle relaxing effect of dipyrone. The inhibitor effect of dipyrone on IP accumulation may be due to direct inhibition of phospholipase C (PLC) or impairment of the activation of PLC by G protein-coupled receptor (GPCR).

Adenosine Triphosphate↗

Does dipyrone have any effect on respiratory function in COPD patients?

OBJECTIVE: Dipyrone (Novalgin) is an effective analgesic, antipyretic agent also with spasmolytic effects on various types of smooth muscles. It has recently been reported that dipyrone relaxes tracheal smooth muscle of guinea pig. In this present study, we aimed to investigate whether this and previously reported in vitro results have any consequences on the respiratory function of normal healthy volunteers and chronic obstructive pulmonary disease (COPD) patients. METHODS: In this one-centered, non-randomized, non-comparative, open labelled study, 15 normal healthy volunteers and 15 stable COPD patients, with partially reversible bronchospasm, diagnosed according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria were enrolled in the study at the time they had any indication of dipyrone use. The spirometric tests were performed by a portable notebook and Medikro Spiro2000 spirometry programme-software 1.6 version, before 30, 60, 90, and 120 min after 20 mg/kg of orally dipyrone intake. Groups were compared with the General Linear Model Repeated Measures analysis of variance. RESULTS: None of the spirometric parameters evaluated showed any significant differences when compared with the baseline values in both groups. CONCLUSION: While dipyrone had no bronchodilator effects on either COPD patients or normal volunteers, it also did not impair the spirometric parameters. Since COPD is a disease characterized by a progressive and largely irreversible airflow limitation, dipyrone has no observable bronchodilator effect. However, since dipyrone does not impair the pulmonary function, it can be used safely in COPD patients when there is an indication.

Adult↗

Reversal of experimental neuropathic pain by T-type calcium channel blockers.

Experimental nerve injury results in exaggerated responses to tactile and thermal stimuli that resemble some aspects of human neuropathic pain. Neuronal hyperexcitability and neurotransmitter release have been suggested to promote such increased responses to sensory stimuli. Enhanced activity of Ca(2+) current is associated with increased neuronal activity and blockade of N- and P-types, but not L-type, calcium channels have been found to block experimental neuropathic pain. While T-type currents are believed to promote neuronal excitability and transmitter release, it is unclear whether these channels may also contribute to the neuropathic state. Rats were prepared with L(5)/L(6) spinal nerve ligation, and tactile and thermal hypersensitivities were established. Mibefradil or ethosuximide was administered either intraperitoneally, intrathecally (i.th.), or locally into the plantar aspect of the injured hindpaw. Systemic mibefradil or ethosuximide produced a dose-dependent blockade of both tactile and thermal hypersensitivities in nerve-injured rats; responses of sham-operated rats were unchanged. Local injection of mibefradil also blocked both end points. Ethosuximide, however, was inactive after local administration, perhaps reflecting its low potency when compared with mibefradil. Neither mibefradil nor ethosuximide given i.th. produced any blockade of neuropathic behaviors. The results presented here suggest that T-type calcium channels may play a role in the expression of the neuropathic state. The data support the view that selective T-type calcium channel blockers may have significant potential in the treatment of neuropathic pain states.

Administration, Topical↗

The role of T-type calcium channels in morphine analgesia, development of antinociceptive tolerance and dependence to morphine, and morphine abstinence syndrome.

Involvement of T-type voltage dependent Ca2+ channels (VDCCs) on morphine antinociception, in the development of tolerance and dependence to morphine, and naloxone-precipitated abstinence syndrome in morphine dependent mice was examined by using mibefradil, a T-type VDCCs blocker. Mice were rendered tolerant and dependent on morphine by subcutaneous (s.c.) implantation of a morphine pellet containing 75 mg of morphine base for 72 hr. The tail-flick test was used to assess the nociceptive threshold. Coadministration of acute mibefradil (10 mg/kg, i.p.) with morphine enhanced the antinociceptive effects of acute morphine. Repeated mibefradil administration (10 mg/kg, i.p., just before, 24 and 48 hr after morphine pellet implantation) completely blocked the development of tolerance to the antinociceptive effect of morphine and even by this effect reached supersensitivity to morphine. However, repeated mibefradil treatment did not alter the development of dependence to morphine assessed by the A(50) values of naloxone (s.c.) required to precipitate withdrawal jumping 72 hr after morphine pellet. But, acute mibefradil (10, 30, and 50 mg/kg, i.p.) dose dependently decreased the expression of morphine abstinence syndrome when given directly 30 min prior to naloxone (0,05 mg/kg, s.c.) 72 hr after morphine pellet. These results indicate a critical role of T-type VDCCs in morphine antinociception, the development of tolerance to the antinociceptive effects of morphine and in morphine abstinence syndrome.

Analgesia↗

The efficacy and safety of dipyrone (Novalgin) tablets in the treatment of acute migraine attacks: a double-blind, cross-over, randomized, placebo-controlled, multi-center study.

Dipyrone, an effective analgesic drug, is widely used in the management of headache. However, few studies have evaluated its efficacy and safety in migraine. We aimed to assess the efficacy and safety of 1 g dipyrone (Novalgin, two 500 mg tablets) on pain and related symptoms in acute migraine attacks with or without aura in a double-blind, cross-over, randomized, placebo-controlled, multi-center study design. Seventy-three migraine with or without aura patients, diagnosed according to the IHS criteria, were randomized to receive dipyrone (for 2 attacks) and placebo (for 1 attack). Pain intensity was measured on a four-point verbal pain scale before and 1, 2, 4 and 24 hours after drug intake. Significant improvement of pain was achieved with dipyrone compared to placebo at all time points measured. Both patient and physician evaluations were significantly in favor of dipyrone. Side effects were few and trivial in both groups. We conclude that dipyrone is an effective, safe and cost-effective option in acute migraine management.

Adolescent↗