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F Block

Publications and source records attributed to F Block.

97 records · Page 6Linked to original sources

S-emopamil ameliorates ischemic brain damage in rats: histological and behavioural approaches.

Transient ischemia induced by 4 vessel occlusion (4VO) in rats is known to produce neuronal damage to particular brain structures such as the CA1 sector of the hippocampus. Behavioural changes associated with ischemic lesioning of this brain region are an impairment in spatial learning of rats tested in a water maze (14). In the present study, it was investigated whether pretreatment with S-emopamil, a Ca2(+)-channel blocker as well as a 5-HT2 antagonist, prevents the occurrence of hippocampal cell damage and/or spatial learning impairments in rats subjected to 4VO. Neuronal lesioning in the hippocampus was significantly reduced following pretreatment with S-emopamil in 4VO rats. In addition, S-emopamil treated animals showed an improved spatial learning ability compared to saline treated 4VO rats. It is suggested that S-emopamil may exert a protective effect under ischemic conditions. The possible mechanisms involved are discussed.

Animals↗

Effects of two isomeric 1-aminoadamantanes on the membrane anisotropy and on alpha- and gamma-motoneurones excitability.

The structure-activity relationship of two isomeric 1-aminoadamantanes, 1-C-ethylaminoadamantane (D 174) and 1-amino-3-ethyladamantane (D 175), on membrane anisotropy and the excitability of neurons was studied in the CNS of the rat and in the decerebrated cat. Mass spectrometric analysis showed that after a single, 40 mg/kg dose, D 174 and D 175 were unevenly distributed within the CNS of the rat, moreover the distribution pattern of the two substances was different. As measured by fluorescence depolarization in controls the membrane anisotropy was found to be higher in the older parts as compared with the younger parts of the CNS. After i.p. application of 40 mg/kg the membrane anisotropy was reduced in the cortex by D 174, whereas D 174 and D 175 increased the rigidity in striatal membranes. If cortical membranes were incubated with the substances, the fluidizing effect of D 174 was more prominent than that of D 175. In the decerebrated cat only D 174 in a dose of 5 mg/kg i.p. raised the discharge of spinal alpha-motoneurones significantly. The results suggest that the membrane architecture is more affected by D 174 as compared with D 175 which is reflected by a greater effect on membrane anisotropy as well as on the activity of spinal alpha-motoneurones.

Adamantane↗

The role of H.I.D.A./P.I.P.I.D.A. scanning in diagnosing cystic duct obstruction.

A newer approach to the early diagnosis of acute biliary tract disease is review. Ninety-two patients were evaluated with a new hepatobiliary agent (H.I.D.A/P.I.P.D.A.) for the presence of cystic duct obstruction. Seven patients with suspected acute gall bladder disease were dropped from the study for the lack of pathologic confirmation of the diagnosis. Forty-four of the remaining 85 patients were subsequently operated on and found to have acute cholecystitis. Forty-three of the 44 had cystic duct obstruction demonstrated on H.I.D.A. Scan (one false negative). An additional 23 patients underwent cholecystectomy for chronic disease. In this group, the gallbladder scan was only 43% (10/23) accurate in correctly identifying disease. Eighteen patients with nonbiliary disease had normal scans. The accuracy of ultrasonography and the scan are also compared in a smaller subgroup of 53 patients who had both studies.

Acute Disease↗

Hyperacute perimesencephalic subarachnoid hemorrhage: demonstration of blood extravasation with MRI.

Perimesencephalic subarachnoid hemorrhage (SAH) is a benign subtype of SAH without known vascular pathology. We report a case of current subarachnoid bleeding in the vicinity of the basilar artery. The patient was on anticoagulation medication and had sustained a head injury 2 days earlier. The bleeding was documented by contrast agent extravasation in MRI. Because of the isointensity of hyperacute blood to CSF in conventional T2 sequences, FLAIR images are mandatory for diagnosis in the hyperacute state.

Acute Disease↗