Investigation of the antioxidant effects of pheniramine maleate and nebivolol on testicular damage in rats with experimentally induced testis torsion

Abstract Purpose: To investigate the biochemical, histopathologic, and spermatogenetic changes in the detorsionated testicle after experimental torsion and to study the antioxidant effects of pheniramine maleate and nebivolol. Methods: Twenty-four Sprague-Dawley male rats were divided into 4 groups: Group 1: Sham; Group 2: Torsion/Detorsion (T/D); Group 3: T/D + Pheniramine maleate (PM); Group 4: T/D + Nebivolol (NB) group. Paroxanase (PON), total antioxidant status (TAS), total oxidant status (TOS), and oxidative stres index (OSI) were measured, and spermatogenetic and histopathologic evaluation was performed in tissue and blood samples. Results: The evaluation of tissue TAS indicated no statistically significant difference in Group 3 compared to Group 2. A statistically significant increase was detected in Group 4 compared to Group 2. Serum PON levels revealed a statistically significant increase in Groups 3 and 4 compared to Groups 1 and 2. The Johnsen testicular biopsy score decreased in Groups 3 and 4, but the decrease was not statistically significant. Conclusions: Pheniramine maleate and nebivolol have antioxidant effects against ischemia-reperfusion damage. They also support tissue recovery, which is more significantly observed by nebivolol.

An unusual dual hypersensitivity reaction to moxifloxacin in a patient

Both immediate and nonimmediate type hypersensitivity reactions (HRs) with a single dose of quinolone in the same patient have not been previously reported. A 47-year-old female patient referred to us because of the history of a nonimmediate type HR to radio contrast agent and immediate type HR to clarithromycin. She experienced anaphylaxis in minutes after the second dose of 50 mg when she was provocated with moxifloxacin. She was treated immediately with epinephrine, fluid replacement and methylprednisole and pheniramine. On the following day she came with macular eruptions, and she was treated with methylprednisolone. The positive patch test performed with moxifloxacin as well as the lymphocyte transformation test proved the T-cell mediated HR. In order to prove the immediate type HR, basophil activation test was performed but was found negative. This case report presents for the first time the 2 different types of HRs in a patient with a test dose of quinolone.

The effect of pheniramine on fentanyl-induced cough: a randomized, double blinded, placebo controlled clinical study / Efeito de feniramina sobre a tosse induzida por fentanil: estudo clínico, randômico, duplo-cego e controlado com placebo

Abstract Background and objectives: There are many studies conducted on reducing the frequency and severity of fentayl-induced cough during anesthesia induction. We propose that pheniramine maleate, an antihistaminic, may suppress this cough. We aim to observe the effect of pheniramine on fentanyl-induced cough during anesthesia induction. Methods: This is a double-blinded, prospective, three-arm parallel, randomized clinical trial of 120 patients with ASA (American Society of Anesthesiologists) physical status III and IV who aged ≥18 and scheduled for elective open heart surgery during general anesthesia. Patients were randomly assigned to three groups of 40 patients, using computer-generated random numbers: placebo group, pheniramine group, and lidocaine group. Results: Cough incidence differed significantly between groups. In the placebo group, 37.5% of patients had cough, whereas the frequency was significantly decreased in pheniramine group (5%) and lidocaine group (15%) (Fischer exact test, p = 0.0007 and p = 0.0188, respectively). There was no significant change in cough incidence between pheniramine group (5%) and lidocaine group (15%) (Fischer exact test, p = 0.4325). Cough severity did also change between groups. Post Hoc tests with Bonferroni showed that mean cough severity in placebo differed significantly than that of pheniramine group and lidocaine group (p < 0.0001 and p = 0.009, respectively). There was no significant change in cough severity between pheniramine group and lidocaine group (p = 0.856). Conclusion: Intravenous pheniramine is as effective as lidocaine in preventing fentayl-induced cough. Our results emphasize that pheniramine is a convenient drug to decrease this cough.

Resumo Justificativa e objetivos: Há muitos estudos sobre a redução da frequência e da gravidade da tosse induzida por fentanil durante a indução da anestesia. Propomos que maleato de feniramina, um anti-histamínico, pode suprimir essa tosse. Nosso objetivo foi observar o efeito de feniramina sobre a tosse induzida por fentanil durante a indução da anestesia. Métodos: Este é um estudo clínico prospectivo, de três braços paralelos, randômico e duplo-cego, de 120 pacientes com estado físico ASA III e IV (de acordo com a Sociedade Americana de Anestesiologistas), ≥ 18 anos e programados para cirurgia cardíaca aberta eletiva sob anestesia geral. Os pacientes foram divididos aleatoriamente em três grupos de 40 pacientes cada, com números aleatórios gerados por computador: grupo placebo, grupo feniramina e grupo lidocaína. Resultados: A incidência de tosse diferiu significativamente entre os grupos. No grupo placebo, 37,5% dos pacientes apresentaram tosse, enquanto que a frequência foi significativamente reduzida no grupo feniramina (5%) e no grupo lidocaína (15%) (teste exato de Fischer, p = 0,0007 e p = 0,0188, respectivamente). Não houve alteração significativa na incidência de tosse entre os grupos feniramina (5%) e lidocaína (15%) (teste exato de Fischer, p = 0,4325). A gravidade da tosse também alterou entre os grupos. Testes post hoc com Bonferroni mostraram que a média da gravidade da tosse no grupo placebo diferiu significativamente das médias dos grupos feniramina e lidocaína (p < 0,0001 e p = 0,009, respectivamente). Não houve alteração significativa na gravidade da tosse entre o grupo feniramina e grupo lidocaína (p = 0,856). Conclusão: Feniramina por via intravenosa tem a mesma eficácia que lidocaína na prevenção da tosse induzida por fentanil. Os resultados enfatizam que feniramina é um medicamento conveniente para diminuir essa tosse.

Anaphylactic Shock Following Intravenous Injection of Cisatracurium and Sufentanil During Anesthesia Induction / 계명의대학술지

Anaphylaxis under general anesthesia is rare but can present as cardiovascular collapse, airway obstruction, and/or skin manifestation. A high level of suspicion is required for the recognition and prompt management and anaphylaxis can be diagnosed through clinical findings. The most common causes of anaphylaxis during general anesthesia are neuromuscular blocking agents, antibiotics, and latex. We present a case of anaphylactic shock following intravenous injection of cisatracurium and sufentanil. The patient was under anesthesia induction and within minutes after injection of these drugs, generalized erythema, bronchospasm, and severe hypotension developed. The Patient was managed with epinephrine, proper hydration, hydrocortisone, and pheniramine and the surgery was decided to be postponed. Subsequent surgery should be performed after conducting skin tests which can help identify the causal agents and determine alternative drugs. Anesthesiologists should be aware that not only expeditious diagnosis and management of anaphylaxis but also further evaluation in order to determine the safe method of subsequent anesthesia.

Antihistamine Pretreatment to Reduce Incidence of Withdrawal Movement After Rocuronium Injection

The purpose of this study was to determine the effectiveness of antihistamine therapy for withdrawal movements caused by rocuronium injection. One hundred seventy one ASA I-II adults undergoing elective surgery were randomly assigned to one of two groups. Patients in the control group (Group C) were premedicated with 2 mL normal saline, and those in the antihistamine group (Group A) were pre-medicated with 2 mL (45.5 mg) pheniramine maleate. After the administration of thiopental sodium 5 mg/kg, rocuronium 0.6 mg/kg was injected. Withdrawal movements were assessed using a four-grade scale. The administration of antihistamine reveals lower grade of withdrawal movement after rocuronium injection.

Measurement of Hemodynamic Changes Caused by Administration of Atracurium Besylate after Pretreatment with Anti-histamine Agent / 대한마취과학회지

BACKGROUND: Hemodynamic changes through the histamine-induced release of atracurium are relatively common, but can be particularly dangerous in hemodynamically unstable patients. This study evaluated the effectiveness of a pretreatment with an anti-histamine agent before the administration of atracurium in the prevention of histamine-induced hemodynamic changes. METHODS: Forty-eight ASA class I and II patients were assigned to four groups. Groups 1 and 2 were assigned to receive atracurium through a bolus 0.5 mg/kg. Groups 3 and 4 were assigned to receive atracurium through a bolus 1.0 mg/kg. Group 1 and 3 were pretreated with pheniramine (H1-blocker) and ranitidine (H2-blocker) intravenously before the induction of general anesthesia. After induction, HemosonicTM 100 was installed and the following hemodynamic parameters were measured: systemic vascular resistance (SVR), cardiac index (CI), heart rate (HR) and blood pressure (BP) immediately before, 1, 2, 3, 5 and 10 min after the rapid administration of the atracurium bolus before the skin incision. RESULTS: Groups 1 and 3 showed more stable hemodynamics than groups 2 and 4. Group 2 showed more significant changes in the SVR, CI, BP, HR than group 1 (P< 0.05). Group 4 showed more significant changes in the SVR, CI, BP, HR than group 3, and some cases were significant hemodynamically (P< 0.05). Group 4 showed more significant changes in the SVR, CI, BP, HR than group 2 (P <0.05). CONCLUSIONS: Pretreatment with an anti-histamine drug prior to the administration of atracurium can be effective in attenuating the hemodynamic responses.

Anti-viral Treatment of Chronic Hepatitis B

Patients with chronic hepatitis B virus (HBV) infection are at risk for development of liver cirrhosis and hepatocellular carcinoma. The goal of antiviral therapy for chronic hepatitis B is the permanent suppression of HBV replication; loss of HBV DNA and HBeAg seroconversion. Three antiviral drugsinterferon, lamivudine and adefovir dipivoxil-are avilable now. Although they were proven to have suppressive effects on HBV replication, their antiviral effects are not satisfactory yet and durability of response is low. Emergence of drug resistant mutants is troublesome in lamivudinr therapy. Expense of drugs is another problem for long-term antiviral treatment. Development of new drugs which have stronger and durable antiviral effects and combination therapy with several antiviral drugs to reduce drug resistant mutants are anticipated.

A Phase II Study of Genexol(R) (paclitaxel) in Metastatic Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Paclitaxel is a very effective agent in the treatment of breast cancer. Samyang Corporation has developed its own process to produce paclitaxel in a large volume using plant cell culture technology. To evaluate the efficacy and safety of Genexol(R) in patients with metastatic breast cancer who have failed to respond to standard therapy, we performed a prospective, multi- center phase II clinical trial. MATERIALS AND METHODS: Patients with metastatic breast cancer were included in this study. Enrollees were required to have histologically confirmed breast cancer with bidimensionally measurable metastatic disease. Genexol(R) was administered at 175 mg/m2 as a 3-hour intravenous infusion every 3 weeks. All patients were premedicated with hydrocortisone, pheniramine maleate, and H2 blocker 30 minutes prior to paclitaxel. We planned to administer at least 4 courses of paclitaxel unless there was disease progression or unacceptable toxicity and to continue treatment up to a total of 6 courses in cases of objective response following 4 courses. RESULTS: The median duration of follow-up was 8.9 (2.07~13.7) months. Forty-five patients were registered and 43 were eligible. The performance status of patients was ECOG 0~1 in 39 patients (90.7%) and 2 in 4 (9.3%). The location of metastases at the start of the study were the lung (15 patients), liver (8 patients), lymph nodes (22 patients), and other (7 patients). Among the 40 evaluable patients, 15 patients obtained partial responses (PRs) (37.5%, 95% CI: 22.5~52.5%). The median duration of response was 11.67 (4.1~11.7) months and the median time to progression was 7.73 (2.8~11.7) months. The median survival time was not reached at 13.7 months, and the overall survival rate at 13.7 months was 70.1%. The hematologic toxicity was primarily neutropenia with grade 3 or 4 in 10 patients (23.3%). The grade 3 or 4 non-hematologic toxicities included alopecia (17, 39.5%), myalgia (2, 4.7%), neuropathy (2, 4.7%), and pruritus (1, 2.3%). Mild hypersensitivity reaction was observed in 2 patients, although it did not cause withdrawal of the test drug. CONCLUSION: The results suggest that the Genexol injection is an effective anticancer formulation for the treatment of metastatic breast cancer and toxicity is acceptable.

A Case of Milk Allergy with Positive Contact Challenge Test / 소아알레르기및호흡기학회지

Food allergy is a state of immunologic reaction resulting from the exposure to food or food additive. The clinical symptoms and signs varied from localized symptoms at the site of direct contact such as contact urticaria, localized gastrointestinal symptoms with nausea, pain, vomiting and diarrhea to systemic symptoms occurring in remote organs, such as skin, respiratory system, cardiovascular system. We reported a case of 8 month-old girl with milk allergy who presented skin symptoms after cutaneous contact with milk protein. Developed after 15 minutes of milk contact challenge on forearm and followed by erythematous papules and wheals distributed throughout the face and neck area accompanied by edema and itching. The symptoms were continued for 2 hours and disappeared after an injection of pheniramine maleate.

A Case of Pheniramine Maleate - Aggravated Chronic Urticaria / 대한피부과학회지

Pheniramine maleate(avil(R)) is a H1-antagonist that is derived from alkylamine. Skin reactions with parenteral administration of avil(R) are uncommon. A 29-year-old woman visited our department with a 3-year history of relapsing generalized multiple pruritic evanescent erythematous wheals after antihistamine and steroid injection. Intradermal skin test with Avil(R) was positive. We treated with 5 mg of mequitazine administration three times a day for 2 years.

The Effects of PolyMem(R) on the Wound Healing

Little objective information is avilable on the influence of occlusive dressings on the healing of cutaneous partial skin defect wounds. Our purpose was to examine the effects of occlusive dressing by using the synthetic dressing mateial, PolyMem in the management of 2nd degree burn wounds and donor sites of split thicknes skin graft and partial-thickness wounds in rabbits. New Zealand white rabbits, 12 to 14 weeks of age, were divided into 2 groups. Two partial thickness skin wounds measuring approximately 40x30 mm were induced using a scalpel on the back of each anesthetized animal. They were designated as group I (dressing with conventional method, n=15), group II (dressing with PolyMen, n=15). Each treated wound was individually covered with the assigned dressing immediately after wounding. Wound were examined and measured at 10 days to determine the extent of healing. By day 10, the PolyMem dressed wounds were approximately 67% healed, while all vaseline gauze dressed wounds were about 50% healed. Standardized 20 mm full-thickness biopsy wounds were treated for 10 days. Section of PolyMem group at POD 10 days showed complete epidermal regeneration above fibrotic dermis (H&E, x40). Section of conventional group at POD 10 days showed marginal epidermal regeneration (H&E, x40). 72 patients (44 patients with 2nd degree burn and 28 patients with skin graft donor sites) were divided into four groups. They were designated as group I (Burn patients with PolyMem, n=24), group II (Burn patients with conventional methods, n=24), group III (S.T.S.G. patients with PolyMem, n=14), group IV (S.T.S.G. patients with conventional methods, n=14). We investigated wound site pain, healing time, comfort and numbers of dressing change. As compared with the control group, the PolyMem dressed group had less pain, more rapid healing time, more comfort, less frequent dressing changes. From these results, we concluded that the occlusive dressing with PolyMem was an effective alternative to the conventional gauze dressig on the wound healing. Our results suggest tat PolyMem is one of the ideal dressing materials.

A Case of Angioedema Probably Induced by Captopril / 대한피부과학회지

Angioedema is a disorder characterized by well-demarcated nonpitting edema involving the tongue, floor of the mouth, larynx, lips, and face. The incidence of angiotensin converting enzyme(ACE) inhibitor related angioedema has been reported to be about 0.1% to 0.2%, and the time of onset is usually during the first week of therapy. These ACE inhibitors include captopril, enalapril, and lisinopril. A 53-year old man with an 8 month history of hypertension previously controlled with atenolol, was presented to the dermatologic department with angioedema of the face and tongue. He had begun therapy with captopril one day before this episode. Even though he was treated with epinephrine and methylprednisolone sodium succinate, the edema gradually progressed and finally dyspnea developed. He was urgently intubated and treated with steroids and pheniramine maleate in the intensive care unit. The edema resolved after 24 hours.

Clinical Analysis of Metastatic Brain Tumors

Several prognostic factors have been implicated in survival prolongation in patients with metastatic brain tumors. Among these, surgery has been regarded as very significant one with respect to life prolongation and improving the quality of survival in such patients. From August 1982 through July 1996, a series of 31 patients with metastatic brain tumors among 785 patients with operated brain tumors, whose medical records, X-rays and follow-ups were avilable, was studied retrospectively to evaluate the beneficial effects of surgery. Despite the limitations inherent to the retrospective study and limited number of patients, we divided these patients into two groups to find out any statistical differences in terms of survival and quality of survival among them: 1) Conservative group(8 nonoperated patients: 5 patients with biopsy or partial resection): 13, and 2) Surgical treatment group(17 totally resected patients: one patient with subtotal resection): 18. The quality of survival was assessed by Karnofsky performance(KP) scale before and after each treatment. The survival of the patients in the surgical treatment group was longer than the conservative treatment group(14.5 months/10 months), but this was not statistically significant(p value: 0.3305). However, improvement of quality of survival, in terms of KP scale, was significantly higher in the surgical treatment group(p value: 0.0027). Although confounded by the lack of controlled, randomized study and limitations of retrospective study, aggressive surgery can be regarded to have a significant role in improving the quality of survival in patients with metastatic brain tumors.

Anesthetic Management in a Patient with Anaphylaxis to Thiopental: A case report / 대한마취과학회지

The incidence of anaphylaxis to intravenous agents used for general anaesthesia is reported as about 1 : 6000. Despite appropriate treatment, mortality is reported as about 6%, thus it is important to try to minimize the risk by prevention. A adequate investigation, communication and avoidance of drugs responsible with the use of pretreatment and alternative techniques, the risk of second reaction should be reduced. A patient who has the history of anaphylactic shock to thiopental, for the induction of anesthesia was scheduled for subtotal gastrectomy. Skin test confirmed that she had a hypersensitivity to a thiopental. We performed combined general and spinal anesthesia. She was premedicated with dexamethasone and pheniramine malate in the operating room. Spinal blockade is up to T6 by 0.5% tetracaine. Then, anesthesia was induced with propofol and midazolam. There is no need for muscle relaxant drugs and anesthesia was maintained with isoflurane, N2O, O2. Subtotal gastrectomy was done without event. Combined general and spinal anesthesia affords the anesthesiologist the opportunity to lower the local anesthetic doses, to avoid using many kinds of intravenous drugs (muscle relaxants, opioids, benzodiazepine, etc.) and to approach a kind of anesthesia that is close to the ideal anesthesia.

A Case of Transfusion Complication under General Anesthesis / 대한마취과학회지

Transfusion complications include ABO/Rh incompatibility, sepsis, febrile reaction, immunosuppression, and viral transmission. We experienced a case of anaphylactic reaction in a 40-year-old male scheduled for laminectomy. Anesthesia was induced by intravenous (I.V.) thiopental sodium and maintained with enflurane / N2O / oxygen. Vital signs were stable until 2 hours into surgery, when patient developed sudden profound hypotension (systolic pressure 60 mmHg) with tachycardia, skin flushing and bronchial wheezing shortly after infusion of only a few milliliters of 4th unit of whole blood. Blood transfusion was immediately stopped, anesthetic agents were discontinued, and 100% oxygen was administered. Rapid administration of I.V. fluids was begun and I.V. hydrocortisone along with pheniramine were administered. Patient was successfully treated and eventually discharged from the hospital. In conclusion, besides hemolytic transfusion reaction, anaphylactic transfusion reaction may cause severe hypotension. One should be aware of the potential for adverse effects including anaphylaxis, should recognize them immediately and treat them appropriately.

Severe forms of neurocysticercosis: treatment with albendazole

Study of 22 patients with the severe form of neurocysticercosis treated with albendazole (ABZ) administered in 6 different schedules ranging from 15 to 30 mg/kg/day for 21 to 60 days. Dextrochloropheniramine and ketoprofen were the adjuvant drugs. Multiple symptoms were observed in 90.9 per cent of patients. Intracranial hypertension was manifested in 90.9 per cent. Hydrocephaly occurred in 86.4 per cent. Evolution was satisfactory in 10 patients, 8 died and 4 had sequelae. Tomographic studies showed the appearance of an isolated IVth ventricle in 9 patients, after ventriculoperitoneal shunt, before ABZ treatment in 3 of them, during in 5 and after treatment in one. Median clinical follow-up duration was 10 months for the patients who died and 3-4 years for survivors. In 3 patients there was an increase in cyst size during the administration of the 15 mg/kg/day ABZ dose, which was not observed in any patient when the 30 mg/kg/day dose was used.

Evaluation of the sedative and some anticholinergic effects of the H1 antagonists loratadine and pheniramine in experimental animals

All antihistaminic drugs have adverse effect of some degree. The most common side effects are sedation and anticholinergic responses. On isolated rabbit jejunum pheniramine [1-2 ug/ml] reduced significantly contraction induced by a submaximal dose of acetylcholine. However, loratadine [1-16 ug/ml] produced no reduction. Loratadine in doses up to [300 mg/kg] which is more than 300 times the effective antihistaminic dose, produced no significant effect on spontaneous motor activity in motor coordination nor in parkinsonism induced by fluphenamine [10 mg/kg: s.c] in adult rats. On the other hand, pheniraine [5 mg/kg] intraperitoneal reduced significantly spontaneous motor activity and motor coordination in experimental rats. Like loratadines, it has no effect on fluphenazine induced parkinsonism. It can be concluded that loratadine is a nonsedating antihistaminic with no peripheral or central anticholinergic effects even in doses 300 times the antihistaminic dose. So, it is a safe and well tolerate

An Experimental Study of the Effect of Histamine on the Human Corpus Cavernosum Tissue / 대한비뇨기과학회지

Histamine is supposed to play an important role to the penile erection mechanisms. We reported that histamine induced a dose-dependent contraction in rabbit corpus cavernosum tissue but in human the exact effect and mechanisms are not established. To investigate the effects of histamine on the corpus cavernosum tissue and the intracellular signal transduction mechanisms, we have studied on the human corpus cavernosum using organ bath and the following results were obtained. 1. Histamine produced no contraction in human corpus cavernosum tissue. 2. In the precontracted tissue by phenylephrine histamine produced dose-dependent relaxation (ED50=2.70x0.00001mol). 3. Histamine-induced relaxation was not dependent on endothelium 4. Histamine-induced relaxation was not affected by administration of pheniramine maleate(0.00001mol), but abolished by cimetidine(0.00001 mol). 5. In the precontracted tissue by phenylephrine histamine produced no relaxation, but pheniramine maleate produced significant relaxation in precontracted tissue. 6. Histamine-induced relaxation was not affected by methylene blue(0.000 01mol), a guanylate cyclase inhibitor, but in a precontracted strip by phenylephrine.forskolin, an adenylate cyclase activator, produced dose-dependent relaxation (ED50=9.34x0.0000001mol). It is concluded that in human, histamine induced dose-dependent relaxation, independent from endothelium, mediated by H2-receptors and cAMP as an intracellular second messenger. The H1-receptors were supposed to be associated with contraction, but distributed in scanty density. By the results of this study, it is supposed that histamine or pheniramine maleate could be used as a drug of intracavernosal injection therapy, but in vivo study and/or in vitro study under electrical stimulation must be preceded.

Histological Changes in Ileal Reservoir Mucosa after Long-term Exposure to Urine / 대한비뇨기과학회지

Mucosal biopsies were obtained for histological and electron microscopical studies from 7 patients with ileal urinary conduit. Shortly after construction of the reservoir there was a reduction in villous height and an increase in crypt depth. After 2 to 3 years of observation, avillous areas were noted in the reservoir mucosa. Electron microscopy shows a loss of microvilli and a reduction of cell construction. The number of mucus-storing goblet cells increased already with in 1 month after construction. No sign of foreign body reaction, dysplasia or metaplasia was encountered. The constant exposure to urine leads to adaptive changes of the reservoir mucosa, resulting in true atropy of villi, crypts, and individual epithelial cells.

An Experimental Study of the Effect of Histamine on the Rabbit Corpus Cavernosum Tissue / 대한비뇨기과학회지

Penile erection is controlled by adrenergic and nonadrenergic-noncholinergic (NANC) neurotransmission. There are many other substances involved in the corpus cavernosum smooth muscle contraction and relaxation. Among them. histamine is supposed to play an important role to the penile erection mechanisms in both human and animals, but the exact effect and mechanisms are not established. To investigate the effects of histamine on the corpus cavernosum tissue and the intracellular signal transduction mechanisms, we have studied on the rabbit corpus cavernosum using organ bath and the following results were obtained. 1. Corpus cavernosum tissue showed contraction in response to histamine in a dose-dependent manner( ED50 = 2.59 x 0.00001mol). 2. Pheniramine maleate ( 0.00001mol), a H1-receptor antagonist, abolished histamine-induced contraction, but cimetidine(0.00001mol), a H2-receptor antagonist, had no effect on histamine- induced contraction. 3. Histamine-induced contraction was abolished by W-7 (0.0001mol), a calmodulin antagonist, but not affected by staurosporine ( 0.0000001mol), a protein kinase C inhibitor. 4. In the precontracted tissue by phenylephrine histamine produced no relaxation, but pheniramine maleate produced significant relaxation in precontracted tissue It is concluded that in rabbit, histamine induced a dose-dependent contraction mediated by H1- receptors and calcium-calmodulin complex as an intracellular second messenger, but there were few H2-receptors in rabbit corpus cavernosum tissue. By the results of this study, it is supposed that histamine or pheniramine maleate could be used as a drug of intracavernosal injection therapy, but human tissue study, in vivo study and/or in vitro study under electrical stimulation must be preceded.