Blood pressure responses to acute or chronic captopril in mice with disruption of bradykinin B2-receptor gene.

OBJECTIVE: To evaluate the role of kinins in the hypotensive response to angiotensin converting enzyme inhibition, we compared the blood pressure effects induced by acute or chronic captopril administration in a mouse strain (Bk2r-/-) with disruption of the bradykinin B2 receptor gene and in wild-type controls (J129 Sv mice). A second aim was to determine whether Icatibant, a selective bradykinin B2-receptor antagonist, prevented the blood pressure changes induced by acute captopril administration in Swiss, c57/B16, J129 Sv and Bk2r-/- mice. METHODS AND RESULTS: Under basal conditions, tail-cuff systolic blood pressure (SBP) and intra-arterial mean blood pressure (MBP) were higher in Bk2r-/- than in J129 Sv (SBP: 132+/-2 versus 113+/-3 mmHg; MBP: 144+/-6 versus 122+/-10 mmHg, P< 0.05 for both comparisons). Acute captopril administration (1 mg/kg body weight, intra-arterially) reduced the MBP of Bk2r-/- and J129 Sv by 36+/-8 and 31+/-7 mmHg, respectively. Swiss and c57/B16 mice showed similar decreases in MBP following captopril. Pretreatment with Icatibant (10 nmol/kg body weight, intra-arterially) did not influence the MBP responses to acute captopril in all the strains. Chronic administration of captopril (approximately 120 mg/kg body weight per day for 2 weeks in drinking water) reduced SBP in either Bk2r-/- or J129 Sv. The magnitude of this response was higher in Bk2r-/- than in J129 Sv (65+/-3 versus 47+/-4 mmHg, respectively, P < 0.01). CONCLUSIONS: Our results suggest that endogenous kinins do not participate in the hypotensive response to angiotensin converting enzyme inhibition in mice; in Bk2r-/-, the exaggerated blood pressure response to chronic captopril appears to be attributable to interference with unbalanced vasoconstrictor action of the renin-angiotensin system.

Effects of tiapride on homovanillic acid levels in human cerebrospinal fluid drawn at pneumoencephalography.

The effect of tiapride on HVA and 5-HIAA levels in the CSF drawn at pneumoencephalography (PEG) was studied. Five consecutive 5 ml fractions of CSF were drawn from control and tiapride-treated subjects. In both groups, a linear increase in HVA concentrations was found between the first and subsequent fractions. On the contrary, no significant difference in 5-HIAA concentrations was found in sequential CSF samples. Tiapride increased the mean HVA concentrations and caused a steeper caudocranial gradient of this metabolite but failed to modify 5-HIAA concentrations. The results suggest that tiapride blocks dopamine (DA) receptors and increases DA synthesis.

Parkinsonism by haloperidol and piribedil.

Three groups of schizophrenic patients were treated with haloperidol, with a low dose of piribedil (a dopamine agonist), and with a combination of the two treatments, respectively. After a few days, all 7 patients treated with the drug combination showed marked rigidity and akinesia, while patients treated with haloperidol alone (4) and piribedil alone (4) showed either mild or no symptoms of parkinsonism. The drug combination induced mainly an akinetic-hypertonic syndrome, while tremors were absent or mild. The results suggest that low doses of the DA-agonist potentiate the extrapyramidal side effects of haloperidol by acting on self-inhibitory DA receptors, thereby blocking the compensatory increase in dopaminergic firing elicited by the neuroleptic agent.

[Bilateral traumatic paralysis of the abducent nerves]. / La paralisi traumatica bilaterale degli abducenti

Two cases of bilateral traumatic abducens palsy are reported. The onset of the ocular symptomatology, several hours after the head injury, suggests a possible involvement of the branches of the meningeal dorsal artery supplying the extradural trait of the 6th cranial nerve.

[Use of stereotaxic surgery in the treatment of hepatolenticular degeneration]. / Impiego della chirurgia stereotassica nel trattamento della degenerazione epato-lenticolare.

The utility and the limits of stereotactic surgery in the treatment of neurological disorders of D.E.L. are discussed in relation to literature data and three personal observations. The operatory results are often unsatisfactory and side-effects and sequelae are frequent as well as relapses. Therefore, the operation must be performed only on those patients, who, in spite of a good general prognosis, are strongly disabled.

Traumatic transdural spinal cord herniation and the nuclear trail sign: case report.

A woman with a history of spine injury in her remote past developed Brown-Sequard syndrome due to a thoracic transdural spinal cord herniation. A clue about the underlying mechanism was offered by the unexpected imaging feature of a nuclear trail sign just below the herniated cord. As suggested by Watters et al., who reported a similar case, this finding is consistent with the hypothesis that intrathecal rupture of disk material could have resulted in an acquired tear of the ventral dural, through which the cord herniated.

Treatment of Sydenham's chorea with a combination of L-dopa and a peripheral dopa decarboxylase inhibitor.

Two male patients suffering from Sydenham's chorea were treated with a combination of L-Dopa and a peripheral decarboxylase inhibitor. This treatment markedly reduced in one patient and totally suppressed in the other the abnormal involuntary movements present in this disease.

Anatomic correlates of painful tonic spasms in multiple sclerosis.

Painful tonic spasms (PTS) are now regarded as a typical symptom of multiple sclerosis but pathologic or radiologic findings rarely have been described. We report clinical and magnetic resonance imaging records of five original cases. In all of them, lesions likely responsible for unilateral PTS involved the motor pathway at the level of the posterior limb of the internal capsule or the cerebral peduncle on the opposite side. Closeness of motor fibers seems to be the most important underlying anatomic factor because it enables involvement of a higher proportion of axons by a single demyelinating lesion and radial spread of ephaptic activation. In turn, preservation of the underlying pyramidal-spinal tract could make it easier for the pathologic discharge to reach the peripheral effectors and generate PTS.

Creutzfeldt-Jakob disease associated with high titer of antithyroid autoantibodies: case report and literature review.

Hashimoto's encephalopathy and Creutzfeldt-Jakob disease (CJD) often have similar clinical features and may be confused, especially at onset. A 61-year-old woman developed rapidly progressive ataxia, myoclonus and dementia, with abnormalities seen on electroencephalography (EEG). Serum analysis disclosed high titers of antithyroid autoantibodies. Both clinical course and autopsy led to a definitive diagnosis of CJD. This case and a literature review of previous cases confirm that CJD may be confused with Hashimoto's encephalopathy. EEG, clinical and laboratory findings (including the positivity of 14.3.3 protein in the cerebrospinal fluid) are not conclusive for a differential diagnosis, especially at early stages. Only the results of genetic exams can allow a definitive diagnosis in a small percentage of cases while patients are still alive. In patients with unclear symptomatology and rapid onset of myoclonus, dementia and ataxia, the presence of antithyroid antibodies should be examined. If their levels are abnormal, corticosteroid therapy remains mandatory.

Chronic delusional hallucinatory psychosis in early-onset Parkinson's disease: drug-induced complication or sign of an idiopathic psychiatric illness?

Chronic delusional psychosis with hallucinations (CDHP) is commonly assumed to complicate the later stages of Parkinson's disease, as a side effect of antiparkinsonian medication. We studied 7 patients with early onset PD, who had developed psychiatric manifestations consisting in CDHP after a few years of antiparkinsonian therapy. All patients underwent a neurological, psychiatric and brain imaging (CT or MRI) evaluation. Detailed clinical history was recorded in order to reveal prior psychiatric illness and to analyse the relationship between neurological disease, cognitive impairment and psychosis. Our findings suggest that CDHP occurring in patients with early onset PD, normal or slightly impaired cognitive functions and normal CT/MRI scans is invariably the expression of a coexisting psychiatric illness which prior to onset of the neurologic disease had not been correctly diagnosed and which has been disclosed by dopaminergic therapy.

Effect of atrazine administration on spontaneous and evoked cerebellar activity in the rat.

The effect of atrazine oral administration on cerebellar forelimb projection area was studied in rats in vivo. Rats acutely treated with atrazine (100 mg kg-1, BW) showed a significant decrease in spontaneous Purkinje cell firing rate. Atrazine also decreased the cerebellar potentials evoked by electrical stimulation of the ipsilateral radial nerve, affecting mostly the response to climbing fiber input. These results demonstrate that atrazine exerts a toxic action on central nervous system. The effects on the cerebellar somatosensory cortex could be responsible for motor disorders frequently observed in animals intoxicated with atrazine.

Bipolar affective disorder and Parkinson's disease: a rare, insidious and often unrecognized association.

Five patients (4 women) with Parkinson's disease (PD) and primary major psychiatric disorder (PMPD) meeting DSM-IV criteria for the diagnosis of bipolar affective disorder (BAD) were studied. Four patients had early onset PD. Four developed a severe psychiatric disorder a few years after starting dopaminergic therapy in presence of a mild motor disability and a mild cognitive impairment, with no evidence of cerebral atrophy at CT or MRI. Two patients developed a clear manic episode; the other three presented a severe depressive episode (in one case featuring a Cotard syndrome). None showed previous signs of long term L-dopa treatment syndrome (LTS), hallucinosis or other minor psychiatric disorders. The two manic episodes occurred shortly after an increase of dopaminergic therapy and in one case rapid cyclic mood fluctuations were observed. At the onset of psychiatric symptoms, all patients had an unspecific diagnosis of chronic delusional hallucinatory psychosis (CDHP).