OBJECTIVETo investigate the effects of intrathecal ouabain and tizanidine injection for treatment of neuropathic pain in rats.

METHODSMale SD rats weighing 250-300 g were randomly divided into 5 groups (n = 6), namely the control group, ouabain group, tizanidine group, combined ouabain and tizanidine injection group, and the antagonist group. Intrathecal catheter was implanted 7 days before spinal nerve ligation to establish the neuropathic pain model. Mechanical withdrawal threshold (MWT) before and after intrathecal administration of the agents was recorded in the rats. Isobolographic analysis was performed to evaluate the interactions between the agents.

RESULTSIntrathecal injection of ouabain (0.25-5 microg) or tizanidine (0.5-5 microg) alone produced dose-dependent analgesic effect against the neuropathic pain (P < 0.05). Isobolographic analysis revealed a synergistic interaction between ouabain and tizanidine. Intrathecal pretreatment with atropine (5 microg) or yohimbine (20 microg) antagonized the effects of ouabain and tizanidine administered alone or in combination (P < 0.05).

CONCLUSIONIntathecal injection of ouabain or tizanidine produces dose-dependent analgesic effects against neuropathic pain, and their synergistic effect after combined injection probably involves the cholinergic transmission and alpha2 receptor.

Analgesics ; administration & dosage ; Animals ; Clonidine ; administration & dosage ; analogs & derivatives ; Injections, Spinal ; Ouabain ; administration & dosage ; Pain ; drug therapy ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spinal Nerves ; injuries

PURPOSE: Fentanyl was reported to inhibit the alpha1-adrenoceptor agonist-induced contraction. The goal of this in vitro study was to identify the alpha1-adrenoceptor subtype primarily involved in the fentanyl-induced attenuation of phenylephrine-induced contraction in isolated endothelium-denuded rat aorta. MATERIALS AND METHODS: Aortic rings were suspended in order to record isometric tension. Concentration-response curves for phenylephrine (10-9 to 10-5 M) were generated in the presence or absence of one of the following drugs: fentanyl (3x10-7, 10-6, 3x10-6 M), 5-methylurapidil (3x10-8, 10-7, 3x10-7 M), chloroethylclonidine (10-5 M) and BMY 7378 (3x10-9, 10-8, 3x10-8 M). Phenylephrine concentration-response curves were generated in the presence or absence of fentanyl in rings pretreated with either 3x10-9 M prazosin, 10-9 M 5-methylurapidil or 3x10-9 M BMY 7378. RESULTS: Fentanyl (10-6, 3x10-6 M) attenuated phenylephrine-induced contraction in the rat aorta. 5-Methylurapidil and BMY 7378 produced a parallel rightward shift in the phenylephrine concentration-response curve. The pA2 values for 5-methylurapidil and BMY 7378 were estimated to be 7.71 +/- 0.15 and 8.99 +/- 0.24, respectively. Fentanyl (10-6 M) attenuated phenylephrine-induced contraction in rings pretreated with 10-9 M 5-methylurapidil, but did not alter the rings when pretreated with 3x10-9 M BMY 7378. Pretreatment of the rings with chloroethylclonidine showed a 72.9 +/- 2.3% reduction in phenylephrine-induced maximal contraction. CONCLUSION: The results suggest that fentanyl attenuates phenylephrine-induced contraction by inhibiting the pathway involved in the alpha1D-adrenoceptor-mediated contraction of the rat aorta.
Adrenergic alpha-Agonists/*pharmacology ; Adrenergic alpha-Antagonists/*pharmacology ; Animals ; Aorta/*drug effects ; Clonidine/analogs & derivatives/pharmacology ; Fentanyl/*pharmacology ; Male ; Phenylephrine/*pharmacology ; Piperazines/pharmacology ; Rats ; Rats, Sprague-Dawley ; Vasoconstriction/*drug effects

The intraocular pressure (IOP) of glaucomatocyclitic crisis with the attack fell 50.3%, from 37.8 +/- 8.2 mmHg to 18.8 +/- 4.8 mmHg, 4 hours after instillation of 1% apraclonidine. Glaucomatocyclitic crisis showed a more significant hypotensive response to 1% apraclonidine than primary open-angle glaucoma (24.8%, from 43. 1 +/- 8.1 mmHg to 32.4 +/- 7.5 mmHg after 4 hours). The intraocular pressure decrease percentage was similar regardless of the initial level of intraocular pressure. Clinically significant changes in mean systolic and diastolic blood pressures, were not observed, however, a mild decrease in the pulse rate was noted. And the local mydriatic effect on the pupillary diameter was significant. Apraclonidine, 1% might be newly indicated to control the IOP rise of glaucomatocyclitic crisis. Further studies on the possible mechanism of the prostaglandin mediated hypotensive effect of 1% apraclonidine are suggested.
Adolescent ; Adrenergic alpha-Agonists/*administration & dosage ; Adult ; Aged ; Clonidine/administration & dosage/*analogs & derivatives ; Female ; Glaucoma, Open-Angle/drug therapy ; Hemodynamics ; Humans ; Intraocular Pressure ; Iridocyclitis/*drug therapy ; Male ; Middle Aged ; Ocular Hypertension/*drug therapy ; Ophthalmic Solutions ; Syndrome

In this study the effects of two unrelated vasodilators, nifedipine and nitroprusside, on the pressor responsiveness to the 1-adrenoceptor full agonist cirazoline and partial agonist Sgd 101/75 in pithed rats were examined. The experiments were performed on the vasoconstriction which was mediated by newly synthetized 1-adrenoceptors after removal of existing 1-adrenoceptors by phenoxybenzamine treatment(5mg/kg, i. p.). The t1/2 for recovery of the maximum response and ED50 of cirazoline were 23.1 +/- 5.5 and 26.9 +/- 7.4 hours, respectively, while that for recovery of the maximum response of Sgd 101/75 was 59.2 +/- 18.9 hours. The relationship between the pressor response and the fractional receptor occupancy for cirazoline showed a rectangular hyperbola. This occupancy-response curve markedly shifted to the right one day after phenoxybenzamine and subsequently returned to the control, indicative of a large receptor reserve. However, for Sgd 101/75 the occupancy-response curve exerted less of a hyperbola and shifited little after phenoxybenzamine. While the maximum response to cirazoline in the control rats was resistant to inhibition by the calcium entry blocker nifedipine, this resistance was significantly reduced one and 3 days after phenoxybenzamine, just as the maximum response to Sgd 101/75 was sensitive to nifedipine in the control rats. Likewise, when nitroprusside was used instead, the results were similar for the cirazoline and Sgd 101/75 effects. In summary, it seems unlikely that the resistance to the calcium entry blocker of the full agonist effect can be wholly ascribed either to the receptor reserves or to the differential calcium utilization itself. Alternatively, it is suggested that the differential resistance to calcium antagonists can result from the magnitude of the variables involved in the activation of 1-adrenoceptor coupling processes depending on the full or partial agonist.
Animal ; Blood Pressure/*drug effects ; Clonidine/*analogs and derivatives/antagonists and inhibitors/pharmacology ; Comparative Study ; Ferricyanides/*pharmacology ; Imidazoles/antagonists and inhibitors/*pharmacology ; Male ; Nifedipine/*pharmacology ; Nitroprusside/*pharmacology ; Rats ; Rats, Inbred Strains ; Vasoconstriction/*drug effects

OBJECTIVETo observe the therapeutic effect of Modified Banxia Houpu Decoction (MBHD) in treating heroin abusers with protracted abstinence syndrome.

METHODSOne hundred and eighty-seven heroin abusers were randomly divided into three groups, the 58 patients in the control group, 62 in the treated group A and 67 in the treated group B. All were detoxified with lofexidine hydrochloride (LFX) tablet for 12 days. MBHD was given to the two treated groups, the medication started from the beginning of detoxification in the group B, and from the end of detoxification in group A for 60 days. To the control group, an imitate preparation was given. The observation was carried out 10 days after withdrawal of medication, and the protracted abstinence related symptoms were observed and scored. And the condition of re-abusing in patients were investigated through urinary examination one year later.

RESULTSThe heroin abusers' protracted abstinence symptom score in the treated group was significantly lower than that in the control group (P < 0.01), and comparison of the scores between the two treated groups also showed significant difference (A < B, P < 0.01). The 1-year re-abusing rate in treated group B was significantly lower than that in the control group and in the treated group A (P < 0.05).

CONCLUSIONMBHD could improve the heroin abusers' protracted abstinence symptoms after detoxification. In spite of the complexity of various factors, to effectively control the early stage abstinence symptoms and median stage protracted abstinence symptoms is one of the effective measures to prevent drug re-abusing.

Adolescent ; Adult ; Clonidine ; analogs & derivatives ; therapeutic use ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Heroin Dependence ; drug therapy ; Humans ; Male ; Narcotic Antagonists ; therapeutic use ; Phytotherapy ; Substance Withdrawal Syndrome ; drug therapy

To determine the effect of apraclonidine hydrochloride on the acute intraocular pressure (IOP) rise after argon laser iridotomy (ALI), a double-masked comparative study was carried out. Twenty-nine eyes (20 patients) with angle-closure glaucoma underwent ALI. Eighteen eyes were treated with apraclonidine, and the remainder received a placebo 1 hour before and immediately after ALI. The mean IOP increase in the apraclonidine group was lower than that in the placebo group at each postlaser interval (p < 0.01). Although the average value of the maximal increases of IOP after ALI in the apraclonidine group was 4 mmHg, that in the placebo group was 16 mmHg. In the placebo group, 27.3% (3 out of 11 eyes) experienced an IOP rise > or = 10 mmHg. However, that kind of IOP rise was not found in the apraclonidine group (0 out of 18 eyes) (p < 0.01). Ocular or systemic side effects were not found in a series of examinations in both groups. Therefore, apraclonidine proved to be effective in lowering the IOP rise after ALI.
Acute Disease ; Adrenergic alpha-Agonists/*pharmacology ; Adult ; Aged ; Clonidine/*analogs & derivatives/therapeutic use ; Double-Blind Method ; Female ; Glaucoma, Angle-Closure/drug therapy/*surgery ; Humans ; Intraocular Pressure/*drug effects ; Iris/drug effects/*surgery ; *Laser Therapy ; Male ; Middle Aged ; Postoperative Complications/prevention & control ; Prospective Studies

PURPOSE: To screen for diabetic autonomic neuropathy of the pupil using 0.5% apraclonidine and 0.1% pilocarpine and to evaluate the early diagnostic value of this pharmacologic pupillary test by assessing the relationship between pupillary and cardiovascular autonomic neuropathies. METHODS: A total of 22 diabetic patients were recruited. Baseline pupillary diameter (PD) and the difference in PD between the test eye and the control eye before and after instillation of apraclonidine and pilocarpine were measured. All patients also underwent cardiovascular autonomic function (CAF) testing. RESULTS: Baseline PD in room light correlated with duration of diabetes mellitus (DM, p=0.049) and the presence of DM retinopathy (DMR, p=0.022). Eleven patients (50%) had positive apraclonidine tests, and two patients had positive pilocarpine tests. The patients who had positive pilocarpine tests also had positive apraclonidine tests. Patients who had a positive pupillary test had a significantly higher rate of positive CAF tests (p=0.032). CONCLUSIONS: Pupillary autonomic neuropathy was related to the duration of diabetes and the degree of DMR. There was also a significant correlation between pupillary autonomic neuropathy and cardiovascular autonomic neuropathy (CAN). Also, sympathetic nerve dysfunction occurred prior to parasympathetic dysfunction in this study. A simple pharmacologic pupillary test can help manage complications in diabetic patients because patients with pupillary autonomic dysfunction have an increased risk of CAN.
Adrenergic alpha-Agonists/administration & dosage/diagnostic use ; Adult ; Aged ; Clonidine/administration & dosage/*analogs & derivatives/diagnostic use ; Diabetic Nephropathies/*diagnosis/physiopathology ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Miosis/*chemically induced/physiopathology ; Miotics/administration & dosage/diagnostic use ; Ophthalmic Solutions ; Pilocarpine/administration & dosage/*diagnostic use ; Pupil/drug effects/*physiology ; Reproducibility of Results