Comparative effects of the antimigraine drugs sumatriptan and ergotamine on the distribution of cardiac output in anaesthetized pigs

The haemodynamic effects of sumatriptan, a 5-HT1-like receptor agonist, and ergotamine, an agonist at alpha-adrenergic, dopamine as well as 5-HT receptors, were compared using intracardiac injection of radioactive microspheres of different sizes in anaesthetized pigs. Ergotamine (0.02 mg.kg-1) and sumatriptan (0.3 mg.kg-1) decreased systemic vascular conductance and cardiac output. Only ergotamine raised arterial blood pressure. Both sumatriptan and ergotamine decreased arteriovenous anastomotic, but not capillary, blood flow in the head and body skin. Arteriovenous and capillary blood flow in the dura mater and nasal mucosa and capillary blood flow in the brain, kidneys, adrenals, intestine, heart, spleen and muscle remained unchanged. However, kidney conductance was decreased by both drugs, spleen conductance by sumatriptan and heart, liver and adrenal conductances were decreased by ergotamine. Thus, both sumatriptan and ergotamine constricted arteriovenous anastomoses in the skin, but not in the dura mater or nasal mucosa. Ergotamine constricted the vasculature more than sumatriptan, although both drugs may differentially decrease vascular conductances in some organs.     

Synthesis and pharmacological screening of some new triazoles

3,5-Dinitrobenzoic acid hydrazide (1) treated with substituted phenyl isothiocyanates (2a-2d) in dry benzene yields N'-aryl-N4-(3,5-dinitrophenyl) thiosemicarbazides (3-6), which cyclizes in NaOH solution yielding 1-aryl-5-(3,5-dinitrophenyl)-2-mercapto-1,3,4-triazoles (7-10). The reaction of the appropriate 7-10 respectively with chloroacetic acid and 4-chlorobenzoic acid in NaOH solution gave 1-aryl-5-(3.5-dinitrophenyl)-2-mercapto methyl/phenyl carboxy-1,3,4-triazoles (11-18). All the compounds were found to be relatively non toxic (ALD greater than 1000 mg/kg), whereas in their gross CNS observations the compounds were found to be psychotropic. They increased or decreased spontaneous locomotor activity and at high doses produced writhing and mild hypothermia. Some of them mildly affected the cardiovascular system and showed antiinflammatory activity.     

Carotid vascular effects of ergotamine and dihydroergotamine in the pig: no exclusive mediation via 5-HT1-like receptors.

1. Though it is well known that the antimigraine drugs ergotamine and dihydroergotamine reduce carotid arteriovenous anastomotic shunting, it is uncertain whether a 5-HT1-like receptor is responsible for this effect. Using a high dose of methiothepin (3 mg kg-1), which completely blocks the carotid vascular effects of sumatriptan, we have attempted to study the role of 5-HT1-like receptors in the carotid vascular effects of ergotamine as well as dihydroergotamine in anaesthetized pigs. 2. Both ergotamine and dihydroergotamine increased arterial blood pressure and decreased heart rate. 3. The ergot alkaloids reduced dose-dependently total carotid blood flow and conductance as a result of a selective decrease in the arteriovenous anastomotic fraction. The nutrient fraction increased, particularly to bones, tongue and salivary glands with ergotamine and to ears, head skin, bones and salivary glands with dihydroergotamine. In contrast, dural vascular conductance tended to decrease. 4. Methiothepin (3 mg kg-1) partially antagonized the decrease in total carotid and arteriovenous anastomotic blood flow and conductance by the ergot alkaloids; the ED30 for ergotamine and dihydroergotamine (agonist dose eliciting a 30% decrease in arteriovenous anastomotic conductance) was raised by 3.1 and 5.2 fold respectively. 5. These results indicate that the effects of ergotamine and dihydroergotamine are partly mediated by methiothepin-sensitive receptors, which may probably belong to either 5-HT1-like or alpha 2-adrenoceptor category. However, an important part of the effect of ergot alkaloids is left after methiothepin and this could be mediated by other, perhaps novel, receptors.     

Unilateral lichen planus

A case of lichen planus with unilateral distribution of lesions is reported in a 26-year-old woman. The patient had no associated neurologic signs or symptoms. The role of neurologic influences in lichen planus is stressed.     

Anterior temporal lobes and hippocampal formations: normative volumetric measurements from MR images in young adults

Volumes of the right and left anterior temporal lobes and hippocampal formations were measured from magnetic resonance images in 52 healthy volunteers, aged 20-40 years. Subjects were selected by age, sex, and handedness to evaluate possible effect of these variables. Data were normalized for variation in total intracranial volume between individuals. Right-left asymmetry in the volumes of the anterior temporal lobes and hippocampal formations was a normal finding. The anterior temporal lobe of the non-dominant (right) hemisphere was larger than the left by a small (mean right-left difference, 2.3 cm3) but statistically significant amount (P less than .005) in right-handed subjects. No significant effect of age or sex was seen in normalized right or left anterior temporal lobe volume. The right hippocampal formation was larger than the left for all subjects by a small (mean right-left difference, 0.3 cm3) but statistically significant amount (P less than .001). No effect of age, sex, or handedness was seen in normalized hippocampal formation volumes.     

Role of computed tomography in unsafe chronic suppurative otitis media

Thirty Patients of Unsafe chronic suppurative otitis media were subjected to pre-operative CT scanning followed by surgical exploration of the middle ear and mastoid, and their scans were compared with the peroperative data. High resolution CT scanning has been advocated for evaluation of unsafe chronic suppurative otitis media as it is capable of delineating detail required to detect Labyrinthine fistulae, Facial canal erosion, Sinus and Dural plate erosion and Ossicular integrity. Our results showed CT scan to be highly sensitive for soft tissue density mass in the middle ear and mastoid. Dural plate exposure, Sinus plate erosion, Facial canal and Stapes integrity, moderately sensitive for Malleus and Incus integrity and least sensitive for Lateral canal fistulae. Both Axial and Coronal scans were done as many important structures are best seen in only one of these planes. The principal merit of CT scan of the Tomporal bone lies in its inherent ability to depict pathology which is not clinically evident.