An Improved Procedure for Catheterization of the Thoracic Spinal Subarachnoid Space in the Rat

Abstract

Catheterization of the subarachnoid space provides a convenient means to deliver drugs to, or collect cerebrospinal fluid from, the spinal cord in animal experiments, and has been instrumental to our understanding of spinal mechanisms that underlie anesthesia, analgesia, or cardiovascular regulation. Experience gained over the years has revealed several shortcomings of this technique. We report a procedure that encompasses the benefits of direct subarachnoid catheterization of the rat thoracic spinal cord but circumvents the known shortcomings. An intrathecal catheter was fabricated with a small silicon bead at one end of a PE-10 catheter, which was cannulated with a 4/0 suture that served as a guide. Using the L-shape hook of the suture guide as an anchorage, the catheter was advanced into the subarachnoid space until the silicon bead was lodged on a drilled hole (2 x 2 mm) over the lamina proper on the T13 vertebrae. With less surgical trauma, greater precision of placement and firmer anchorage of the catheter, less leakage of cerebrospinal fluid, and minimal mortality or morbidity, our modified procedure for catheterization of the thoracic spinal subarachnoid space in the rat compared favorably to previously reported methods.

Catheterization of the thoracic spinal subarachnoid space in mice

“…This well-documented pathway in central cardiovascular regulation was used as a functional assessment of the thoracic subarachnoid catheterization. As we demonstrated previously in rats (Poon et al, 2005), subarachnoid application of a NMDA blocker, MK801 (75 nmol), given at a volume of 3 L, depressed significantly MAP and power density of LF or VLF component of the SBP spectrum, without affecting HR (Fig. 3).…”

“…On removal of the intraspinous ligaments between T12 and T13, an obvious intervertebral space was exposed with a large enough plane for catheterization. We further adopted several measures from our successful thoracic spinal catheterization in rats (Poon et al, 2005). First, we selected the shortest possible length of catheter to reach the target site.…”

DIFFERENTIAL CONTRIBUTION OF N-METHYL-d-ASPARTATE AND NON-N-METHYL-d-ASPARTATE RECEPTORS IN THE INTERMEDIOLATERAL CELL COLUMN OF THE THORACIC SPINAL CORD TO SYMPATHETIC VASOMOTOR TONE DURING EXPERIMENTAL ENDOTOXEMIA IN THE RAT

“…Animals used in our physiological experiments were instrumented with an indwelling intrathecal catheter using an improved procedure that our laboratory devised for catheterization of the thoracic spinal subarachnoid space in the rat (18). Briefly, rats were anesthetized with intraperitoneal injection of pentobarbital sodium (50 mg kg j1 ), and a hole (2 Â 2 mm) was drilled over the middle portion of the left T13 lamina proper until the dura was exposed.…”

An improved method for protecting and fixing the lumbar catheters placed in the spinal subarachnoid space of rats

“…In order to protect the external portion of the catheter, several methods were developed and employed by researchers. Such as the catheter was tunneled under the skin to the cervical region (Størkson et al, 1996;Pogatzki et al, 2000;Wu et al, 2004) or buried the exterior part of the catheter under the skin and retrieved it through a small incision under local anesthesia (Poon et al, 2005). Among them, catheter was tunneled under the skin to the cervical region was frequently used.…”