Bromocriptine scientific update |
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Auton Autacoid Pharmacol. 2007 Apr;27(2):123-9.
Balthazar CH, Ribeiro Oliveira A Jr, Marubayashi U, dos Reis AM, Coimbra CC.
Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Av. Antonio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
Chronic treatment with bromocriptine modifies metabolic adjustments in response to restraint stress in rats.
1. We investigated the influence of bromocriptine (BR) chronic treatment in the autonomic adjustments to energetic
metabolism during restraint stress (RS). To achieve this, Wistar male rats were chronically treated with BR before
the application of RS. The rats were divided into two groups: those treated with BR and control rats, treated with
saline. 2. Chronic treatment with BR did not affect rat growth and induced a 20% higher basal plasma glucose
concentration. During RS, BR rats presented higher plasma glucose concentrations than the control animals. Despite
this, the 30-min analysis of the areas under the glucose curve showed that the control rats presented a
hyperglycemic response to RS two-fold greater than the BR rats. 3. RS induced an increase in plasma lactate
concentration in both groups of rats; however, the 30-min analyses under the lactate curves showed that BR rats
presented a lactate response to RS three times higher than control rats. 4. RS induced an increase in plasma free
fatty acids (FFA) concentration in both groups; however, plasma FFA concentration of BR rats returned to the basal
values at the end of RS. In contrast, in the control group, this concentration continued to rise until the end of
RS. 5. The results showed that BR chronic treatment shifts the balance of substrate utilization in response to RS,
suggesting that the essential role of lactate in the metabolism homeostasis may be altered by chronic BR treatment.
Psychopharmacology (Berl). 2007 Apr 28;
Srikumar BN, Raju TR, Shankaranarayana Rao BS.
Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), PB# 2900, Hosur Road, Bangalore, 560 029, India
Contrasting effects of bromocriptine on learning of a partially baited radial arm maze task in the presence and absence of restraint stress.
RATIONALE: Severe, traumatic stress or repeated exposure to stress can result in long-term deleterious effects,
including hippocampal cell atrophy and death, which, in turn, result in memory impairments and behavioural
abnormalities. The dopaminergic D(2) receptor agonist, bromocriptine, has been shown to modulate learning, and
chronic stress is associated with dopaminergic dysfunction. OBJECTIVES: In the present study, we evaluated the
effects of bromocriptine in the presence or absence of restraint stress. MATERIALS AND METHODS: Adult male Wistar
rats were subjected to restraint stress for 21 days (6 h/day) followed by bromocriptine treatment, and learning was
assessed in the partially baited radial arm maze task. In a separate group of animals, the effects of bromocriptine
per se was evaluated. Dopamine levels were estimated by high-performance liquid chromatography with electrochemical
detection. RESULTS: Stressed rats showed impairment in both acquisition and retention of the radial arm maze task,
and bromocriptine treatment after stress showed a reversal of stress-induced impairment. Interestingly, in the
absence of stress, bromocriptine exhibited dose-dependent differential effects on learning. While rats treated with
bromocriptine 5 mg/kg, i.p., demonstrated impairment in learning, the bromocriptine 10 mg/kg and vehicle-treated
groups did not differ from normal controls. To understand the neurochemical basis for the effects of bromocriptine,
dopamine levels were estimated. The stress-induced decrease in dopamine levels in the hippocampus and frontal
cortex were restored by bromocriptine treatment. In contrast, bromocriptine alone (5 mg/kg, i.p.) decreased
dopamine levels in the frontal cortex and striatum. CONCLUSIONS: Our study shows that amelioration of
stress-induced learning impairment correlates with restoration of dopamine levels by bromocriptine treatment.
Zhonghua Wai Ke Za Zhi. 2006 Nov 15;44(22):1555-7.
Zhang HW, Yu CJ, Sun W, Yang J, Yan CX, Cun EH.
Department of neurosurgery, Beijing Sanbo Fuxing Brain Hospital & Fuxing Hospital, Affiliated to the Capital University of Medical Sciences, Beijing 100038, China.
[Bromocriptine treatment of invasive giant prolactinomas prior to comprehensive treatments: results of a long-term follow up][Article in Chinese]
OBJECTIVE: To observe long-term outcomes of patients with invasive giant prolactinomas (IGPs) treated with
bromocriptine followed by comprehensive treatments. METHODS: Thirty-four patients met the criteria of IGPs were
treated with bromocriptine initially. Among of them, 11 had radiotherapy at the same time. During the treatments,
transsphenoidal surgery or/and Gamma Knife were considered to apply to the patients according to the location,
shrinkage of residual tumors and resistance of bromocriptine. Small dosage of bromocriptine was kept after
operation. RESULTS: The average follow-up duration is 33.6 months. Thirty-three patients obtained significant
improvement, but one failed recovery of vision due to side-injury by radiotherapy. Tumor volume on magnetic
resonance imaging (MRI) was decreased on average by 91.4%, PRL by 97.1%. The number of patients with low
testosterone level restored from 17 to 6 and hypoadrenalism from 10 to 6 after combined treatment with priority of
medical therapy. Rhinorrhea occurred in 2 cases, 1 restored in two weeks, 1 had transsphenoidal combined with
transcranial surgery to remove the tumor and repair the fistula.4 had resistance to bromocriptine to some extend.
CONCLUSIONS: Dopamine agonist medications are effective as a first-line therapy for IGPs. In some patients treated
by bromocriptine only, the tumor may disappear on MRI. Combined with surgery and Gamma Knife, the duration of
treatment could be shortened and the dosage may be minimized, but using radiotherapy should be cautions.
Can J Neurol Sci. 2007 Mar;34 Suppl 1:S118-24.
Freedman M.
Division of Neurology and Rotman Research Institute, Baycrest.
Frontotemporal dementia: recommendations for therapeutic studies, designs, and approaches.
Frontotemporal dementia (FTD) is one of three neurobehavioural syndromes produced by frontotemporal lobar
degeneration. Despite the importance of FTD as a cause of dementia, especially in younger age groups, and a
rationale for therapies targeting serotonergic and dopaminergic systems, there have been no large scale treatment
trials in FTD. Moreover, there is no consensus on standards to facilitate comparison across therapeutic trials.
This paper reviews the literature on therapeutic trials in FTD and outlines general recommendations for standards
related to the development of future treatment studies in this disorder. Drugs tested in FTD include trazodone,
galantamine, idazoxan, lithium plus fluoxetine, lithium plus paroxetine, SSRIs, 1-deprenyl, moclobemide,
methylphenidate, piracetam, rivastigmine, donepezil, olanzapine, risperidone, amantadine, guanfacine, allopurinol,
and bromocriptine. Improvement has been reported in FTD for all drugs except piracetam, guanfacine and galantamine,
although there was improvement on galantamine in primary progressive aphasia. Whereas improvement has been reported
for paroxetine and other SSRIs, as well as idazoxan and methylphenidate, paroxetine and idazoxan have also been
reported to cause a decline in function, and a marginally significant decline has been reported for
methylphenidate. In addition, patients with Pick's disease, which is part of the spectrum of frontotemporal lobar
degeneration, showed improvement on calcium EDTA. Six studies are double-blind placebo-controlled trials: two
reports of cases using idazoxan and group trials using trazodone, paroxetine, galantamine and methylphenidate. It
is recommended that experts in FTD arrive at a consensus to define standards for all clinical trials in FTD. These
should include standards for diagnostic criteria, tests of severity, experimental design, and outcome measures.
Hormones (Athens). 2003 Jul-Sep;2(3):183-5.
Lambrinoudaki IV, Daskalaki OD, Thomopoulos SA, Schinochoritis P, Argyropoulos AB.
2nd Department of Obstetrics and Gynecology, University of Athens, School of Medicine, "Aretaieion" Hospital, Athens, Greece.
Macroprolactinemia. Is treatment necessary?
A 26-year old symptom-free woman was admitted to our Clinic for evaluation of hyperprolactinemia. The patient, who had normal menstrual cycles, was found accidentally to have a cystic adnexal mass and was placed on oral contraceptives (OC) for 3 months. During the first OC-cycle a bilateral breast nipple discharge was noticed and an elevated serum prolactin (PRL) was detected (2.7 nmol/l). The OC was discontinued and bromocriptine therapy was started. Serum PRL levels were restored and spontaneous menses resumed. The Pituitary magnetic resonance imaging (MRI), the anterior pituitary function, assessed by dynamic tests, and the thyroid hormone levels were normal. Upon bromocriptine discontinuation, PRL levels increased to 13.8 nmol/l. Poly-ethylene-glycol precipitation of the patient's serum, in two consecutive measurements, demonstrated the presence of macroprolactinemia. Since the patient was asymptomatic, a dopamine agonist was not resumed. Macroprolactinemia is characterized by most authors, as a benign condition with no clinical implications. However, a number of investigators challenge this view, suggesting that in some cases mild symptomatology is present possibly requiring therapeutic intervention.
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Drug category:Antiparkinson agents
 Bromocriptine scientific update
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