An in situ brain perfusion technique to study cerebrovascular transport in the rat

Abstract

The right cerebral hemisphere of the rat was perfused in situ by retrograde infusion of HCO3 saline or blood into the right external carotid artery. Infusion rate was adjusted to minimize the contribution of systemic blood to flow in the hemisphere. During perfusion with whole or artificial blood, regional cerebral blood flow and blood volume were comparable to respective values in the conscious rat, whereas perfusion with HCO3 saline increased regional flow three- to fourfold due to the low viscosity of the saline perfusate. Perfusion with whole blood for 300 S or with HCO3 saline for 60 S did not alter the permeability of the blood-brain barrier. Cerebrovascular permeability coefficients of eight nonelectrolytes ranged from 10(-8) to 10(-4) cm X S-1 and were directly proportional to the octanol-water partition coefficient of the solute. Thus the in situ brain perfusion technique is a sensitive new method to study cerebrovascular transfer in the rat and permits absolute control of perfusate composition.

Transport of Biogenic Amine Neurotransmitters at the Mouse Blood–Retina and Blood–Brain Barriers by Uptake1 and Uptake2

“…Surgical procedure and perfusion: We assessed the functional role of mediated carriers systems by measuring the transport of selected labeled compounds at the brain and eye of mice by in situ carotid perfusion, in which the blood is completely replaced by an artificial perfusion fluid for a very short time (Cattelotte et al, 2008;Smith, 1996;Takasato et al, 1984). Mice were anesthetized with ketamine-xylazine (140-8 mg/kg, intraperitoneally) and the appropriate vessels were ligated.…”

“…A catheter was inserted into the right common carotid artery and connected to the perfusion system. The thorax was opened, the heart was cut, and perfusion was started immediately at a constant flow rate (2.5 mL/ min) and pressure (Cattelotte et al, 2008;Takasato et al, 1984). Perfusion was terminated by decapitation and the brain and the right eye were removed from the skull; the brain was dissected out on a cold freezer pack, and the eye on dry ice.…”

“…The relative permeability of the luminal barriers for each compound was measured by comparison with that of [ 3 H]-diazepam, which is freely diffusible. Extraction E (%) values are given by: (Cattelotte et al, 2008;Takasato et al, 1984).…”

Clonidine Transport at the Mouse Blood—Brain Barrier by a New H+ Antiporter that Interacts with Addictive Drugs

“…The second perfusion was with or without DPH (10 mmol/L) (pH e 6.40) for 60 secs. Apparent brain distributional volume and initial brain transport parameters: All calculations were carried out as described earlier (Smith, 1996;Takasato et al, 1984). The brain vascular volume was estimated using the [ 14 C]sucrose distribution volume (V v ; mL/g), as sucrose diffuses across the BBB very slowly: …”

“…We measured the transport of [ 3 H]clonidine at the luminal membrane of the endothelial cells that form the mouse BBB by in situ brain perfusion. This method can accurately determine BBB permeability and it is possible to control the composition of the vascular perfusate for a short time (Cattelotte et al, 2008;Smith, 1996;Takasato et al, 1984). We used exposure to various chemicals and ions, together with studies on transporter knockout (KO) mice, to identify the properties of clonidine transport at the mouse BBB.…”