Anterior pituitary hormone levels in the cerebrospinal fluid of patients with pituitary and parasellar tumors

Neuropsychological complications of hypoprolactinemia

Prolactin (PRL) is primarily produced by the pituitary lactotrophic cells and while initially named for its role in lactation, PRL has several other biological roles including immunomodulation, osmotic balance, angiogenesis, calcium metabolism, and appetite regulation. Most of the PRL-related literature has traditionally focused on hyperprolactinemia, whereas hypoprolactinemia has received little attention. There is evidence to suggest that PRL receptors are widely distributed within the central nervous system including the limbic system. Furthermore, PRL has been shown to play key role in the stress regulation pathway. Recent data also suggest that hypoprolactinemia may be associated with increased sexual dysfunction, anxiety, and depression. In this paper we discuss the current understanding regarding the neuropsychological impact of hypoprolactinemia and highlight the need for adequately defining hypoprolactinemia as an entity and consideration for future replacement therapies.

Mixing and modes of mass transfer in the third cerebral ventricle: a computational analysis

Anatomic, velocimetric, and brain motion MRI scans were combined with a computational fluid dynamics model to investigate cerebrospinal fluid (CSF) mixing in the third cerebral ventricle of a healthy male adult. It was found that advection dominates over diffusion in most of the third ventricle. Three zones where diffusion plays an important role in the mixing process were identified. One of these zones, consisting of recessus infundibulus, recessus opticus and the adjacent regions up to commissura anterior, is likely to exist in the general population. We hypothesize that this zone may act as a buffer to flatten concentration peaks of pituitary gland hormones released into the CSF of the third ventricle. We further hypothesize that this zone may facilitate the communication between hypothalamus and the pituitary gland through the third ventricle cerebrospinal fluid by prolonging residence times of the communicated hormones.

Adenohypophyseal hormone levels in the cerebrospinal fluid of patients with pituitary disease

Measurement of adenohypophyseal hormones in the cerebrospinal fluid (CSF) was recently proposed as an useful procedure to differentiate pituitary intra and extrasellar tumors. So far, data reported are conflicting. We measured the concentrations of GH, TSH, LH and PRL in CSF and plasma in 30 controls and in 37 patients with various pituitary diseases (18 intrasellar adenomas, 14 extrasellar adenomas and 5 empty sella syndromes). The concentrations of examined hormones in CSF were very low or undetectable in all control subjects. In most patients with pituitary tumors, adenohypophyseal hormones were found to be present in CSF, in great amounts. No significant differences were found between intra and extrasellar tumors. In agreement with recently reported data, no significant correlation was found between GH, TSH, FSH and LH levels in CSF and plasma, while a significant correlation (p less than 0.01) was obtained between CSF and plasma levels of PRL, either in all patients or in those with extrasellar tumors only. All patients bearing an empty sella had PRL detectable in CSF: in 2 cases PRL levels were very high. In conclusion our data do not confirm that measurement of adenohypophyseal hormones in CSF represents an useful screening to differentiate tumors with extrasellar extension. PRL data deserve interest in order to gain understanding of the hormone dynamics between CSF and vascular compartments.