Immediate allergic response in small airways

The role of small airways in the immediate allergic response is largely unknown. We therefore used the model of precision-cut lung slices (PCLS) in combination with quantitative videomicroscopy to study the early allergic response to allergen in airways ranging from 50 to 900 microm. After PCLS from untreated Wistar rats had been passively sensitized for 16 h with serum from sensitized Brown Norway rats, exposure to 0.1% ovalbumin resulted in an immediate allergic response. Both extent (r = 0.74, p < 0.0001) and velocity (r = 0.49, p < 0.0001) of the allergen-induced bronchoconstriction increased with decreasing airway size. In addition, we observed that smaller airways not only contracted stronger and quicker, but that they also relaxed faster, suggesting that smaller airways are more reactive in principle. The allergen-induced bronchoconstriction in PCLS was prevented by the serotonin receptor antagonist ketanserin (IC(50) 6 nM), but not by antagonists directed against histamine, acetylcholine, PAF, or endothelin receptors, or by cyclooxygenase or lipoxygenase inhibitors. Like allergen, serotonin provoked responses that were stronger in smaller airways. These findings suggest that the immediate allergic response in rat PCLS depends largely on serotonin and that this response can occur in nearly all airway generations, but is most pronounced in the smallest airways, that is, the terminal bronchioles.

Ketanserin for the treatment of preeclampsia

OBJECTIVE

To compare maternal and perinatal outcome with the use of either intravenous ketanserin or dihydralazine in treatment of women with preeclampsia.

METHODS

The records from January 1989 to January 1997 of all patients receiving intravenous ketanserin or dihydralazine as first line antihypertensive therapy were reviewed and standardized data forms were completed. 315 charts of patients were identified and evaluated for effects on blood pressure, laboratory parameters, maternal and perinatal outcome.

RESULTS

During the study interval 169 patients received ketanserin and 146 dihydralazine. Significantly fewer antepartum (27% versus 38%, p = 0.04) and postpartum (25% versus 39%, p = 0.01) maternal complications were noted in patients receiving ketanserin. Occurrence of HELLP syndrome was significantly lower among patients who received ketanserin (20%) than among those who received dihydralazine (40%, p = 0.0001). Side-effects were reported with significantly higher frequency in patients receiving dihydralazine (60%) as compared to those receiving ketanserin (17%, p < 0.0001). Perinatal outcome was comparable, however, umbilical cord arterial pH values (mean +/- SD) were higher with ketanserin compared to dihydralazine (7.25 +/- 0.07 vs 7.23 +/- 0.09, p = 0.038). The incidence of placental abruption was higher in patients receiving dihydralazine (5.5%) versus those receiving ketanserin (0.6%, p = 0.014).

CONCLUSION

Ketanserin appears to be a better option than dihydralazine for treatment of severe preeclampsia since fewer maternal complications and side-effects were observed in patients receiving ketanserin.

Blood pressure patterns in pregnant patients on oral ketanserin

BACKGROUND

Ketanserin, a selective serotonin-2 receptor antagonist, decreases systolic blood pressure (SBP) and diastolic blood pressure (DBP) in non-pregnant patients with hypertension, but not in normotensive subjects. Its effect on longitudinal blood pressure (BP) patterns in pregnant women has not been documented.

OBJECTIVES

To assess how ketanserin, given orally, influences maternal BP during pregnancy.

DESIGN

A double-blind randomised controlled trial where patients with DBP > or =80 mmHg between 12 and 20 weeks' gestation received either ketanserin or placebo.

SETTING

Tygerberg Hospital, a tertiary referral unit in the Western Cape.

SUBJECTS

One hundred and two patients who received their study drug for at least 140 days during pregnancy. Patients requiring additional antihypertensive medication were excluded from the analysis.

OUTCOME MEASURES

Changes in SBP and DBP in relation to gestational age and days since entering the study.

RESULTS

The mean DBP over the total period was significantly lower in the ketanserin group (77 +/- 8.7 mmHg v. 80.8 +/- 9.1 mmHg). The decline in DBP was 9.2 mmHg in the ketanserin group and 5.3 mmHg in the placebo group. These differences were detected from within 7 days of therapy and persisted for most of the pregnancy. The mean SBP did not differ at any stage, although the mean fall in SBP was significantly greater in the ketanserin group (8.6 +/- 16.7 v. 4.1 +/- 17.1 mmHg).

CONCLUSIONS

Ketanserin decreased DBP during pregnancy significantly more than placebo.

Use of topical ketanserin for the treatment of ulcers in leprosy patients

A comparative study was carried out in which 66 leprosy patients with ulcers were randomly divided in two groups of 33 patients each: Group A (experimental group) was treated with ketanserin gel (2%) and group B with clioquinol cream and/or Lassar paste during a three month period. At the end of the study, when ulcer sizes in the two groups were compared, the group treated with topical ketanserin showed superior results (p < 0.001 using Kolmogorov-Smirnov's test). We conclude that the drug is useful as coadjuavant treatment for healing ulcers in these patients.

Pharmacological treatment of severe hypertension in pregnancy and the role of serotonin(2)-receptor blockers

Hypertensive disorders of pregnancy are the leading cause of maternal and perinatal mortality and morbidity in developing and developed countries. The etiology of preeclampsia is still unknown. Delivering the baby is the only definite treatment. The benefits of acute pharmacological control of severe hypertension prior to and/or post-delivery are generally accepted. Most drugs commonly used in the management of severe hypertension in pregnancy have significant maternal and/or neonatal adverse side effects. Furthermore, some are not effective to acutely lower the blood pressure in patients with a hypertensive crisis. Until recently not one of the commonly used antihypertensive drugs has been tailored to the pathophysiology of severe preeclampsia, being a clinical syndrome characterized by endothelial cell dysfunction, vasospasm and platelet aggregation. Ketanserin, a serotonin(2)-receptor blocker, is a drug that appears to be tailored for treating this pregnancy-associated enthothelial cell dysfunction. The results of several prospective trials show that there is a definite place for serotonin(2)-receptor blockers in the treatment of pregnancy-induced hypertensive disorders. This review provides a summary on the more established drugs as well as on some of the newer antihypertensive drugs used in pregnancy with emphasis on the existing experience with ketanserin.

Effect of the serotonin antagonists ritanserin and ketanserin in Cushing's disease

Central serotonergic regulation could have a role in the course of pituitary-dependent Cushing's disease. We studied the effects of ritanserin and ketanserin, two related selective 5HT2 receptor antagonists, in 11 patients with Cushing's disease. Treatment lasted from 1 month to 1 year (up to 4 years in one patient). Daily doses were 10-15 mg for ritanserin, and 40-80 mg for ketanserin. Since the two drugs share the same mechanism of action and no qualitative or quantitative differences in response to their administration were observed, the results were pooled together. Patients were assessed by clinical and hormonal evaluation. Urinary cortisol and ACTH were considered the parameters of interest. Short-term response: after 1 month, there was a significant decrease of urinary cortisol from 781 (160) to 331 (215) nmol/d (P < 0.02) while ACTH was 9.8 (1.5) pmol/L baseline and again 8.8 (2.2) pmol/L at 1 month (P = NS). For 9 patients, hormonal parameters were available after 1 week of treatment. In this case, also ACTH levels were significantly decreased (from 9.6 (1.7) to 5.2 (1.3) pmol/L; P < 0.01) together with urinary cortisol (from 781 (194) to 372 (165) nmol/d; P < 0.01). Long-term response: in 3 patients, hormonal parameters failed to respond to serotonin receptor antagonists, which were thus discontinued. An improvement was recorded in the remaining 8 patients, that was prolonged in 3, and transient in 5. In 3 of these latter patients, a marked increase of ACTH was observed before treatment discontinuation. Ketanserin was given to 2 patients with Nelson's syndrome, with only transient ACTH decrease in one, and no changes in ACTH response to CRH after 1 month treatment in both cases. An inhibitory effect of ritanserin and ketanserin on ACTH and cortisol production in Cushing's disease appeared to be limited both in terms of duration of response and number of patients with a satisfactory outcome. However, the results may provide a better understanding of serotonergic modulation in Cushing's disease and lead to therapeutic developments.

Serotonin antagonism and serotonin antagonists in pregnancy: role of ketanserin

Most agree that antihypertensive medication should be used to treat severe hypertension during pregnancy, but its role in patients with mild to moderate disease is debated. None of the regularly used drugs is completely safe for mother and fetus. Ketanserin decreases systolic and diastolic blood pressure in nonpregnant patients with acute and chronic hypertension. Its selective serotonin S2-receptor antagonist activity encouraged investigations into a possible role in pregnant women. These reports can be divided into four groups. Several studies confirmed that intravenous ketanserin decreases blood pressure significantly in patients with severe preeclampsia. There are indications that it may be at least as effective as dihydralazine, possibly with fewer side effects. Its role in chronic hypertension has not been studied adequately, but one randomized, controlled trial indicated efficacy comparable with that of alpha-methyldopa. Thirdly, it was concluded in a single descriptive study that the administration of ketanserin to patients with HELLP syndrome allowed delivery to be postponed for 5.3 days. Lastly, in a randomized, placebo-controlled trial, the addition of ketanserin to aspirin in patients with mild to moderate midtrimester hypertension was associated with a significant decrease in the number of cases of preeclampsia and severe hypertension, as well as a trend to less perinatal mortality, lower rates of abruptio placentae, and early-onset preeclampsia. Additional studies are needed to adequately assess a possible role for ketanserin with acute hypertension or moderate chronic hypertension.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians

LEARNING OBJECTIVES

After completion of this article, the reader will be able to list the various drugs and their associated side effects that are used to treat hypertensive disorders during pregnancy; to describe the various effects of serotonin on the cardiovascular system; to summarize the literature concerning the use of ketanserin during pregnancy; and to list the potential uses of ketanserin in this setting.

Ketanserin inhibits digoxin-induced arrhythmias in the anaesthetized guinea-pig

Digoxin inhibits the membrane-bound ATPase enzyme, resulting in a rise in intracellular sodium and activated outward potassium current, predisposing to arrhythmias. In this study, the effect of ketanserin, thought to block outward potassium currents, was investigated on digoxin-induced arrhythmias. Twenty-four guinea-pigs were studied in four groups (control, ketanserin 0.5 mg/kg, ketanserin 1 mg kg, ketanserin 2 mg/kg). Under pentobarbital anaesthesia (40 mg/kg), 15 min after injection of saline or ketanserin, digoxin (0.6 mg/kg) was administered through the jugular vein. Carotid artery blood pressure and electrocardiogram (ECG) were recorded. The time for the onset of the first arrhythmia and incidence of ventricular tachycardia (VT), ventricular fibrillation (VF), and premature ventricular contraction (PVC) were determined. Arrhythmias were scored according to the MacLeod scale. Ketanserin produced minor haemodynamic effects and lacked, by itself, arrhythmogenic effects at the doses studied. However, it increased the time for the onset of the first digoxin-induced arrhythmia and decreased the incidence of VT, VF and PVC. We conclude that ketanserin inhibits digoxin-induced arrhythmias in guinea-pigs.

Ketanserin for Raynaud's phenomenon in progressive systemic sclerosis

OBJECTIVES

To assess the effects and toxicity of the following agent: ketanserin versus placebo proposed for the treatment of Raynaud's phenomenon (RP) in scleroderma.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register, and Medline up to 1996 using the Cochrane Collaboration search strategy developed by Dickersin et al.(1994). Key words included: Raynaud's or vasospasm, scleroderma or progressive systematic sclerosis or connective tissue disease or autoimmune disease. Current Contents were searched up to and including April 7, 1997. All bibliographies of articles retrieved were searched and key experts in the area were contacted for additional and unpublished data. The initial search strategy included all languages.

SELECTION CRITERIA

All randomized controlled trials comparing ketanserin versus placebo were eligible if they reported clinical outcomes of interest. Trials with dropout rates greater than 35% were excluded.

DATA COLLECTION AND ANALYSIS

Data were abstracted independently by two reviewers (DF, AT). Peto's odds ratios (OR) were calculated for all dichotomous outcomes, and a weighted mean difference (WMD) was carried out on all continuous outcomes. A fixed effects or random effects model were used if the data was homogeneous or heterogeneous, respectively.

MAIN RESULTS

Three trials and 66 patients were included. The proportion improved was significantly better in the group on ketanserin with an odds ratio (OR) of 4.80 (95% CI 1.33, 17.37). However, when comparing ketanserin to placebo, the decrease in severity of RP attacks favoured placebo but this was not statistically significant. Side effects were significantly more common in the group using active treatment with an OR of 5.96 (95% CI 1.61, 22.06). Frequency of attacks did not change, but the duration of attacks decreased significantly in the ketanserin group.

REVIEWER'S CONCLUSIONS

Ketanserin may have some efficacy in the treatment of Raynaud's phenomenon secondary to scleroderma. Overall, ketanserin is not significantly different from placebo for the treatment of Raynaud's phenomenon except for some decrease in the duration of attacks and more subjects improved on ketanserin compared to placebo. However, there were more side effects. It can be concluded that ketanserin treatment in Raynaud's phenomenon secondary to scleroderma is not clinically beneficial.

Topical ketanserin gel for anal fissure: an open-label, prospective study

This open-label, prospective study assessed the efficacy and safety of topical ketanserin gel in 63 patients with symptomatic anal fissure. The efficacy outcome was total clinical healing of the fissure. Topical ketanserin gel was 90% effective (fissure healed) and 100% safe (no adverse events) in the primary nonsurgical treatment of anal fissure.

Intracoronary ketanserin augments coronary collateral blood flow and decreases myocardial ischemia during balloon angioplasty

AIMS

To test the hypothesis that ketanserin augments coronary collateral blood flow and decreases myocardial ischemia during balloon angioplasty.

METHODS AND RESULTS

Forty-four patients with single vessel disease and stable angina were studied. Collateral flow was determined during balloon inflations, based on the distal velocity time integral (13 patients) or on coronary wedge/mean arterial pressure measurements (10 patients). The 2nd and 3rd inflations lasted the same time and between them 1.5 mg intracoronary ketanserin in 10 ml normal saline was administered over 3 min. In 21 control subjects normal saline alone was given. In the flow velocity group the velocity time integral was 78.5+/-53.1 mm during the 2nd inflation and 106.0+/-43.2 mm during the 3rd (p<.05), while the ST deviation was 1.1+/-.7 and .7+/-.7 mm, respectively (p<.05). In the intracoronary pressure group the CWP/MBP was .40+/-.10 during the 2nd inflation and .45+/-.11 during the 3rd (p<.05), while the ST deviation was 1.2+/-.8 and .8+/-.8 mm respectively (p<.05). In the controls no variables changed during the tested inflations.

CONCLUSION

Intracoronary administration of ketanserin augments coronary collateral flow and decreases myocardial ischemia during balloon angioplasty. This could be of clinical significance in the management of acute ischemic syndromes.

Hyperalgesia due to nerve damage: role of nerve growth factor

The hypothesis that nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) contribute to hyperalgesia resulting from nerve damage was tested in rats in which the sciatic nerve was partially transected on one side. Administration of antisera raised against NGF and BDNF relieved mechanical and thermal hyperalgesia in these animals. It has been suggested that NGF may elicit hyperalgesia by inducing mast cells to release algesic agents such as serotonin (5-HT). We found that degranulation of mast cells with compound 48/80 relieved mechanical and thermal hyperalgesia produced by nerve damage. We also found that local injection of the 5-HT2A and 5-HT3 receptor antagonists ketanserin and ICS 205-930 into the affected hind paw relieved mechanical hyperalgesia in a dose-dependent fashion. These findings support the idea that in this rat model of hyperalgesia due to peripheral nerve damage, NGF acts on mast cells to induce release of 5-HT, which sensitizes nociceptors. Hyperalgesia due to nerve injury and hyperalgesia due to inflammation may share some common features.

Ketanserin versus dihydralazine in the management of severe early-onset preeclampsia: maternal outcome

OBJECTIVE

An open, randomized, prospective, multicenter trial was conducted to compare the efficacy and safety of intravenous ketanserin, a selective serotonin 2 receptor blocker, with that of intravenous dihydralazine in the management of severe early-onset (<32 weeks' gestation) preeclampsia. End points of this study were blood pressure control and maternal outcome.

STUDY DESIGN

Patients with a diastolic blood pressure >110 mm Hg were randomly assigned to receive either ketanserin (n = 22) or dihydralazine (n = 22) as initial therapy. Plasma volume expansion preceded antihypertensive treatment, which was administered according to a fixed schedule.

RESULTS

The reductions in blood pressure with the 2 drugs were similar; however, adequate blood pressure control was reached significantly earlier with ketanserin (84 +/_ 63 vs 171 +/- 142 minutes, P = .017). Occurrence of maternal complications was significantly lower among patients who received ketanserin than among patients who received dihydralazine (n = 6 vs n = 18, P =.0007). A significant difference in favor of ketanserin was noted in daily fluid balance.

CONCLUSION

Antihypertensive efficacies of ketanserin and dihydralazine were comparable, but significantly fewer maternal complications were noted among the patients receiving ketanserin. Ketanserin is an attractive alternative in the management of severe early-onset preeclampsia.

The haemodynamic effects of ketanserin versus dihydralazine in severe early-onset hypertension in pregnancy

OBJECTIVE

To compare the haemodynamic efficacy of ketanserin (a selective serotonin2-receptor blocker) with dihydralazine in the management of severe early-onset hypertension in pregnancy.

DESIGN

Subgroup analysis within a randomised prospective multicentre trial to compare haemodynamic effects as measured by pulmonary artery catherization.

SETTING

Departments of Obstetrics and Gynaecology and Intensive Care Medicine, Free University Hospital, Amsterdam and Sophia Hospital, Zwolle.

PARTICIPANTS

Thirty-one women with a diastolic blood pressure > 110 mmHg and a gestational age between 26 and 32 weeks.

RESULTS

The antihypertensive efficacy of both drugs was comparable. Dihydralazine significantly increased cardiac output (P < 0.01), while ketanserin induced only minor changes in cardiac output. Systemic vascular resistance decreased in both groups, but the decrease was significantly more pronounced with dihydralazine compared with ketanserin. Ketanserin induced a significant but not clinically relevant increase in heart rate (P < 001, while dihydralazine caused marked tachycardia (P < 0.005). Left ventricular stroke work index was reduced to similar values in both groups.

CONCLUSIONS

The antihypertensive profile of ketanserin is characterised by an early and gradual reduction of blood pressure in combination with a moderate decrease in systemic vascular resistance and no significant change in cardiac output. Dihydralazine causes market tachycardia resulting in a considerable increase in cardiac output.

Long-term effects of erythropoietin on platelet serotonin storage and platelet aggregation in hemodialysis patients with reference to ketanserin treatment

Correction of uremic platelet serotonin (5-HT) storage pool deficiency is one of the very early hemostatic effects of erythropoietin (Epo) therapy. In this work, platelet 5-HT with relation to primary hemostasis was studied in 15 hemodialysis patients treated with Epo for 8 months. Moreover, effects of ketanserin, a blocker of platelet and vascular smooth muscle cell 5-HT2A receptors, in these patients were followed. The parameters studied were compared with relevant values in healthy controls and in hemodialysis patients not treated with Epo, and remeasured in the long-term Epo patients after a 14-day oral ketanserin trial. Platelet 5-HT content in the eighth month of Epo therapy was not different from the one in untreated patients. Ristocetin- and collagen-induced platelet aggregation were enhanced in comparison with both control groups, as opposed to unaltered response to ADP and arachidonic acid. Fibrinogen concentration was lower than in the untreated group. An inverse correlation between ADP-induced platelet aggregation and the skin bleeding time (r=-0.536, p<0.05) and a positive one between the former and platelet 5-HT (r=0.644, p<0.01) were found. Platelet count correlated positively with both platelet 5-HT (r=0.823, p<0.0002) and ADP-induced platelet aggregation (r=0.596, p<0.02). Ketanserin produced a decrease in ristocetin-induced platelet aggregation, fibrinogen, and prolongation of the bleeding time. The first two of the changes correlated positively with their pre-ketanserin values (r=0.923, p<0.00001 and r=0.839, p< 0.0001, respectively). Post-ketanserin, positive correlations between depressed ristocetin- and arachidonic acid-induced platelet aggregation (r=0.760, p<0.005), and between collagen- and corresponding values of arachidonic acid- (r=0.622, p<0.02), ADP-induced platelet aggregation (r=0.396, p<0.01), and platelet 5-HT (r=0.654, p<0.05) were found. Efficient hemostasis in hemodialysis patients on protracted Epo therapy is, in part, dependent on enhanced platelet aggregability. Correction of platelet 5-HT storage pool deficiency is not evident in this stage but 5-HT still influences complex mechanisms of primary hemostasis. Ketanserin is of anticoagulant value in these patients but its effects must be weighted against possible exacerbation of the anemia.

The PACK trial: morbidity and mortality effects of ketanserin. Prevention of Atherosclerotic Complications

A total of 3899 patients over 40 years old who had documented intermittent claudication for at least 2 months and in whom the ratio of systolic blood pressure in the ankle to that in the arm was < 0.85 in both arteries of at least one foot were recruited in a double-blind, randomized, placebo-controlled trial after a single-blind run-in period of placebo treatment for 1 month. Trial drug was ketanserin 40 mg three times daily. The first primary event after randomization was the endpoint. Primary events were definite myocardial infarction, major stroke, amputation above the ankle, excision of ischaemic viscera, and death due to other vascular causes. There were 136 study endpoints in the 1930 patients treated with ketanserin, who were followed up for 2063 patient-years, and 132 study endpoints in the 1969 patients treated with placebo, who were followed up for 2129 patient-years. A harmful interaction of ketanserin and potassium-losing diuretics resulted in an increase in the number of deaths. After patients taking potassium-losing diuretics or antiarrhythmic agents were excluded, a secondary analysis showed that there were 65 endpoints in 1514 patients taking ketanserin and 87 in 1577 patients taking placebo, a reduction of 23% in the number of study endpoints in those taking ketanserin. The treadmill walking distance and ankle systolic pressure were measured in a predetermined subset of 594 patients. Complete datasets at the beginning and end of 1 year's treatment with ketanserin or placebo were available in 436 patients. There was no difference between the groups in the improvement in pain-free treadmill walking distance. The placebo effect on treadmill walking distance increased continuously for at least 1 year at the rate of about 15% every 6 months. There was no significant change in either group in the ankle systolic pressure at the end of the treatment period, but, in the group given ketanserin, brachial systolic pressure was decreased and the ankle/arm systolic pressure ratio therefore increased.

The modified Rodnan skin score is an accurate reflection of skin biopsy thickness in systemic sclerosis

OBJECTIVE

To test the ability of the modified Rodnan skin score to reflect skin thickness in skin biopsies from 141 patients with systemic sclerosis (SSc) obtained at entry during a prospective, double blind study of ketanserin versus placebo in SSc.

METHODS

Punch skin biopsies (4 mm) were obtained from the dorsal surface of the distal forearm of 141 patients. Biopsy specimens were trimmed and weighed (wet weight) and then desiccated and reweighed (dry weight). Skin score was recorded for 17 areas, graded 0-4+, while edema was graded 0-4+ in 10 of the same sites using finger pressure.

RESULTS

Total skin score correlated with wet weight (r = 0.553) and dry weight (r = 0.517) of the skin biopsies. Local skin score from the biopsied forearm also correlated with wet and dry weight (r = 0.536 and 0.530, respectively). Dry weight as a percentage of wet weight was the same for diffuse cutaneous SSc (dSSc) and limited cutaneous SSc (lSSc) (30.7% for both, NS), despite increased wet weight in patients with dSSc versus lSSc (17.75 vs 13.03 g; p < 0.001). Edema scores correlated poorly both with wet weight (r = 0.069) and dry weight (r = 0.169).

CONCLUSION

Total and forearm skin score correlates well with both wet and dry forearm skin biopsy weight from forearm biopsies, indicating that skin score reflects the underlying pathology of SSc. Further, the percentage of dry to wet weight is similar for lSSc and dSSc, supporting the usefulness of skin score in differentiating SSc disease subtypes.

Chronic UVA (365-nm) irradiation induced scratching in hairless mice: dose-time dependency and the effect of ketanserin

In a study on the dose-response relationship for longwave UVA (UVA1; 340-400 nm) carcinogenesis in hairless mice scratch marks appeared after months of daily exposure as an unwanted side effect. Tumor induction in the highest of the 4 tested dose groups (receiving a daily dose of 430 kJ/m2 of 365-nm radiation) could not be determined because extensive scarification occurred prior to the development of any tumors. The induction of scratch marks could be scored and quantified in all 4 dose groups tested. The UVA1 dose-dependencies for the induction of tumors and scratch marks were compared. We found that the induction of scratch marks depended mainly on the cumulative UVA1 exposure, whereas tumor induction showed a lesser dose-dependency. An attempt was made to prevent the apparent pruritogenic effect of UVA1 irradiation and to understand its mechanism. The influence of ketanserin, a serotonin/histamine antagonist, on the UVA1 induction of scratch marks was tested in groups of 8 mice daily irradiated with 430 kJ/m2. No difference was found between treated and untreated animals. Histological examination of skin biopsies from irradiated mice from the 430-kJ/m2 dose group from the UVA1 carcinogenic experiment, showed no changes in numbers of mast cells or other inflammatory features when compared to skin biopsies from unirradiated control mice. This indicated that UVA1-induced scratching is not mediated through mast cell release of serotonin and/or histamine. An adequate therapeutic treatment which can prevent UVA1-induced scratching would enable us to test tumor induction with UVA1 over a larger dose range, and may provide additional insight in how this radiation damages the skin. It remains conjectural whether there exists an analogous UVA-induced pruritus in human skin.

Dihydralazine or ketanserin for severe hypertension in pregnancy? Preliminary results

OBJECTIVE

To compare the efficacy and safety of intravenous dihydralazine with ketanserin in the management of severe hypertension in the third trimester.

STUDY DESIGN

A double blind randomised controlled trial, comparing 5 mg dihydralazine with 10 mg ketanserin after an intravenous infusion of 500 ml of a crystalloid solution. Medication was repeated every 20 min till the therapeutic goal of 90 mm Hg was reached, to a maximum of 4 dosages. Main outcome measures were treatment failures and emergency deliveries for fetal distress.

RESULTS

The therapeutic goal was met more often in patients receiving dihydralazine (36/38 compared to 27/42; P < 0.01). The need for delivery for fetal distress did not differ (3 after dihydralazine, 1 after ketanserin, P = 0.29) No therapy related perinatal loss occurred, but one mother with an undiagnosed phaechromocytoma died 24 h after receiving dihydralazine.

CONCLUSION

Ketanserin in this dosage is less effective to lower diastolic blood pressure. The place of a fluid load prior to dihydralazine needs to be further investigated, as fetal heart rate decelerations were less common than previously reported.

A randomized multicenter double-blind comparison of urapidil and ketanserin in hypertensive patients after coronary artery surgery

OBJECTIVES

To compare the hemodynamic responses, safety, and efficacy of urapidil and ketanserin in hypertensive patients after coronary artery surgery.

DESIGN

Randomized double-blind study.

SETTING

Multi-institutional.

PARTICIPANTS

One hundred twenty-two patients undergoing elective coronary artery surgery.

INTERVENTIONS

When hypertension (defined as mean arterial pressure > 85 mmHg) developed within the first 2 hours after arrival in the intensive care unit, patients received urapidil (n = 62) or ketanserin (n = 60) to reach a mean arterial pressure between 65 and 75 mmHg. Urapidil was administered by repeated bolus injections (25 to 125 mg) followed by a continuous infusion of maximally 50 micrograms/kg/min. Ketanserin was administered by repeated bolus injections (10 to 50 mg) followed by a continuous infusion of maximally 4.0 micrograms/kg/min.

MEASUREMENTS AND MAIN RESULTS

A complete hemodynamic profile was determined at baseline and at 30 and 60 minutes after start of study medication. In the urapidil group, mean arterial pressure (+/-SD) decreased significantly from 100.6 +/- 12.4 mmHg at baseline to 74.6 +/- 12.1 mmHg at 30 minutes and 73.5 +/- 13.8 mmHg at 60 minutes. In the ketanserin group, mean arterial pressure decreased significantly from 98.7 +/- 10.7 mmHg at baseline to 83.5 +/- 16.8 mmHg at 30 minutes and 83.1 +/- 15.3 mmHg at 60 minutes. Between the groups, there was a significant difference in the degree of lowering mean arterial pressure at 30 and 60 minutes. Heart rate increased significantly by 5.8 +/- 12.7 (30 minutes) and 8.6 +/- 16.5 (60 minutes) beats/min in the ketanserin group. In the urapidil group, no changes in heart rate occurred. Cardiac output increased to the same extent (0.7 L/min) in both groups. Within and between the groups, there were no relevant changes in pulmonary filling pressures. The number of patients not responding adequately to the study medication (mean arterial pressure > 85 mmHg after 30 minutes despite the maximum doses of study medication) was comparable in both groups (9 [U] v 13 [K]). Adverse events attributable to the study medication occurred to a similar degree in both groups. In the patients treated with urapidil, a significantly higher incidence (32.3%) of hypotension (mean arterial pressure < or = 65 mmHg for more than 10 minutes) occurred after 60 minutes of continuous infusion.

CONCLUSIONS

In contrast to ketanserin, urapidil did not increase heart rate. Urapidil was more effective in lowering arterial blood pressure than ketanserin. However, one third of the patients treated with urapidil developed hypotension after 60 minutes of continuous infusion.

Haemodynamic effects of ketanserin either alone or with oxygen in COPD patients with secondary pulmonary hypertension

To indirectly test the hypothesis whether serotonin (5-HT) might have a role in the increase in pulmonary vascular resistance, we evaluated the haemodynamic and gas exchange response of intravenous ketanserin (K), a 5-HT receptor inhibitor, in eight severe but stable patients with chronic obstructive pulmonary disease with secondary pulmonary hypertension (mean pulmonary artery pressure (Ppa) 30.3 +/- 7.3 mmHg). Measurements were done at baseline, after oxygen breathing (2 L.min-1), K bolus (6-15 mg) and finally during oxygen breathing (2 L.min-1) added to K infusion (3-6 mg.h-1). K bolus induced a significant reduction of mean Ppa (p < 0.05), mean systemic arterial pressure (p < 0.01) and total systemic resistance (p < 0.01). Cardiac index (+7%), oxygen delivery (+7%) and pulmonary vascular resistance (magnitude of the reduction: -12%) did not change significantly. When oxygen was added to K infusion, the cardiac index significantly dropped when compared to K bolus (p < 0.05), but oxygen delivery remained stable because of the resulting increase in arterial oxygen concentration; against baseline, the mean Ppa showed the same magnitude of reduction as with oxygen breathing or K bolus alone (p < 0.05). Ventilation and gas exchange were not significantly influenced by K bolus. When we individually analysed the changes of pulmonary vascular resistances by plotting the driving pressure through the pulmonary circulation against the cardiac output, we observed that an active vasodilating effect on the pulmonary circulation occurred with K in only one patient, while in three other patients there was rather a recruitment effect of the pulmonary vessels due to the systemic effects of the drug. In conclusion, this study of a small number of patients with severe chronic obstructive pulmonary disease associated with pulmonary hypertension shows that the parenterally given serotonin antagonist ketanserin predominantly affects the systemic circulation. Our results do not support the hypothesis that in stable chronic obstructive pulmonary disease patients with pulmonary hypertension, serotonin might have a role in the increase of pulmonary vascular tone.