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An inexpensive rotating connector for chronic intragastric infusion
Physiology & Behavior, Vol. 25, pp. 183--184. Pergamon Press, 1982. Printed in the U.S.A.
An Inexpensive Rotating Connector for Chronic Intragastric Infusion P. D. BRYANT,* S. S. A L P E R T t
A N D W. F. W O O D S I D E *
*Department of Pharmacology, University of New Mexico School of Medicine and tDepartment of Physics and Astronomy, University of New Mexico, Albuquerque, N M 87131 R e c e i v e d 28 D e c e m b e r 1981 BRYANT, P. D., S. S. ALPERT AND W. F. WOODSIDE. An inexpensive rotating connectorfor chronic intragastric infusion. PHYSIOL. BE HAV. 29( 1) 183--184, 1982.--This paper describes the construction of a watertight rotating connector which is made from inexpensive materials. The connector is suitable for long term intrngastric infusion in freely moving rats. Rotating connector
Watertight swivel joint
Intragastric infusion
T H E R E are several techniques available for chronic intragastric infusion of freely moving rats [1, 2, 6, 7]. AH require the use of a watertight swivel connector to prevent twisting and kinking of the tube connected to the animal. Commercial connectors are available but are expensive. There are several swivel connectors that can be made from inexpensive materials [3, 4, 8]. Our swivel connector is simpler to construct than the previously described inexpensive swivels because it is made from readily available parts that require only slight modification. Construction time is about five minutes per swivel connector. The swivel is made from a 14 ga. 2 inch (2.1 mm 5.1 cm) Angiocath (also referred to as an over-the-needle IV catheter) and a PRN adapter (male luer IV adapter with a rubber injection port). Both components are commonly used in clinical medicine and are manufactured by the Deseret Company, Sandy, UT 84070. They should be readily available from a local medical supply house. The components of the swivel are shown in Fig. 1 (see legend of figure for details) and the steps for construction are outlined below. 1. Cut offlower 5 cm from the protective sheath (Fig. 1). 2. Discard green inner sleeve from the protective sheath. 3. Cut stainless steel needle 6 cm above point. 4. Heat portion o f stainless steel needle that remains in plastic hub to melt glue so that the needle can be removed without damaging the plastic hub. 5. Cut off upper 1.2 cm from plastic hub. 6. Re-insert stainless steel needle into plastic hub so that the needle extends 2.5 cm below hub. 7. Using a cyanoacrylate adhesive (Super Glue, Woodhill Permatex Co., Cleveland, OH 44128) reglue the needle into the hub. 8. With a '/16 inch (1.6 mm) bit, drill a hole in the center of the rubber cap of the PRN adapter. 9. Put PRN a d a p t e r into the modified protective plastic sheath and insert needle into hole in rubber cap of PRN adapter and snap hub in plastic sheath.
C o p y r i g h t © 1982
PLASTICHUB~ ¢.
b STAINLESSSTEEL-NEEDLE
! I
PRN ADAPTER~ --0
SHEATH
A
B
C
FIG. 1. A: PRN adapter and angiocath parts required to construct swivel joint, before modification described in text. B: Angiocath parts after modification and PRN adapter. C: Assembled swivel.
Pergamon Press---0031-9384/82/070183-02503.00/0
184
BRYANT, ALPERT AND WOODSIDE
~
~.['\,
~
TUBE FROM PUMP
/SWIVEL
STAINLESS STEEL HYPODERMICNEEDLE --STAINLESS STEEL SPRING
TUBE TO ANIMAL
FIG. 2. Assembled swivel mounted in three-fingered clamp with stainless steel connector and flexible stainless steel spring attached.
The swivel is lubricated by applying a drop of polysorbate 80 (Tween 80, United States Biochemical Corporation, Cleveland, OH 44128) to the rubber cap of the PRN adapter.
A stainless steel hypodermic needle connects the PRN adapter to the tube going to the animal (Fig. 2). The tube is protected from the animal by being enclosed within a flexible stainless steel spring (o.d. 0.155 inch 3.96 mm, i.d. 0.119 inch 3.00 mm; Projector Recording Belt Company, Whitewater, WI 58190) which is soldered to the stainless steel hypodermic needle. The swivel is mounted in a three-prong clamp so that the PRN adapter is the only part that turns. The swivel is cleaned as needed by flushing with warm water to remove any deposits that might impede flow. After each cleaning the swivel should be lubricated with polysorbate 80 so that it turns without excessive resistance. The swivel connector has been used successfully for chronic intragastric infusion of rats [5] and for chronic intracerebral infusion of mice (R. A. Selinfreund, Department of Anatomy, University of New Mexico Medical School, personal communication). Due to the relatively large dead space (0.33 ml), the swivel connector as described is less suitable for intravenous infusion of drugs. However, the following modification allows reduction of the dead space to approximately 0.10 ml. Remove the plastic liner holding the rubber cap on top of the PRN adapter and then remove the cap. Cut off 1.6 cm of the adapter and slide the rubber cap back on the shortened adapter. Stretch a small piece of teflon tape around the cap to hold it on tightly and to reduce friction.
ACKNOWLEDGEMENTS This work was supported by HEW-NIH grant 5-P-5OHP1132704 and by NIH grant 2507RRO7185-02.
REFERENCES I. Allsop, J. R. and J. F. Burke, Constant access to the circulation and intestinal tract of the unrestrained rat. J. Surg. Res. 25: l l l - l l 8 , 1978. 2. Altar, A. A chronic subcutaneous gastric cannula in adult rats. Pharmac. Biochem. Behav. 12: 629-631, 1980. 3. Darracq, C., P. Gonzalez and C. Balabaud. Double and single swivel joints for infusion and/or body fluid collections of free moving animals. Physiol. Behav. 25: 327-329, 1980. 4. Epstein, A. N. and P. Teitelbaum. A watertight swivel joint permitting chronic injection into moving animals. J. appl. Physiol. 17: 171-172, 1962.
5. Hayek, A., P. D. Bryant, L. Paxton and W. F. Woodside. Hypernatremia induces hypedipemia and a fatty liver. Clin. Res. 30: 137A, 1982. 6. Nicolaidis, S., N. Rowland, M.-J. Meile, P. Marfaing and A. Pesez. A flexible technique for long term infusion in unrestrained rats. Pharmac. Biochem. Behav. 2: 131-136, 1974. 7. Novin, D., M. Rezek and D. A. Vanderwelle. A cannula for infusion and withdrawal of fluids in unrestrained animals. Physiol. Behav. 12: 135-136, 1974. 8. Thomas, D. W. and J. Mayer. A simple and inexpensive swivel joint for the infusion of unrestrained animals. Physiol. Behav. 3: 499-500, 1968.
An Inexpensive Rotating Connector for Chronic Intragastric Infusion P. D. BRYANT,* S. S. A L P E R T t
A N D W. F. W O O D S I D E *
*Department of Pharmacology, University of New Mexico School of Medicine and tDepartment of Physics and Astronomy, University of New Mexico, Albuquerque, N M 87131 R e c e i v e d 28 D e c e m b e r 1981 BRYANT, P. D., S. S. ALPERT AND W. F. WOODSIDE. An inexpensive rotating connectorfor chronic intragastric infusion. PHYSIOL. BE HAV. 29( 1) 183--184, 1982.--This paper describes the construction of a watertight rotating connector which is made from inexpensive materials. The connector is suitable for long term intrngastric infusion in freely moving rats. Rotating connector
Watertight swivel joint
Intragastric infusion
T H E R E are several techniques available for chronic intragastric infusion of freely moving rats [1, 2, 6, 7]. AH require the use of a watertight swivel connector to prevent twisting and kinking of the tube connected to the animal. Commercial connectors are available but are expensive. There are several swivel connectors that can be made from inexpensive materials [3, 4, 8]. Our swivel connector is simpler to construct than the previously described inexpensive swivels because it is made from readily available parts that require only slight modification. Construction time is about five minutes per swivel connector. The swivel is made from a 14 ga. 2 inch (2.1 mm 5.1 cm) Angiocath (also referred to as an over-the-needle IV catheter) and a PRN adapter (male luer IV adapter with a rubber injection port). Both components are commonly used in clinical medicine and are manufactured by the Deseret Company, Sandy, UT 84070. They should be readily available from a local medical supply house. The components of the swivel are shown in Fig. 1 (see legend of figure for details) and the steps for construction are outlined below. 1. Cut offlower 5 cm from the protective sheath (Fig. 1). 2. Discard green inner sleeve from the protective sheath. 3. Cut stainless steel needle 6 cm above point. 4. Heat portion o f stainless steel needle that remains in plastic hub to melt glue so that the needle can be removed without damaging the plastic hub. 5. Cut off upper 1.2 cm from plastic hub. 6. Re-insert stainless steel needle into plastic hub so that the needle extends 2.5 cm below hub. 7. Using a cyanoacrylate adhesive (Super Glue, Woodhill Permatex Co., Cleveland, OH 44128) reglue the needle into the hub. 8. With a '/16 inch (1.6 mm) bit, drill a hole in the center of the rubber cap of the PRN adapter. 9. Put PRN a d a p t e r into the modified protective plastic sheath and insert needle into hole in rubber cap of PRN adapter and snap hub in plastic sheath.
C o p y r i g h t © 1982
PLASTICHUB~ ¢.
b STAINLESSSTEEL-NEEDLE
! I
PRN ADAPTER~ --0
SHEATH
A
B
C
FIG. 1. A: PRN adapter and angiocath parts required to construct swivel joint, before modification described in text. B: Angiocath parts after modification and PRN adapter. C: Assembled swivel.
Pergamon Press---0031-9384/82/070183-02503.00/0
184
BRYANT, ALPERT AND WOODSIDE
~
~.['\,
~
TUBE FROM PUMP
/SWIVEL
STAINLESS STEEL HYPODERMICNEEDLE --STAINLESS STEEL SPRING
TUBE TO ANIMAL
FIG. 2. Assembled swivel mounted in three-fingered clamp with stainless steel connector and flexible stainless steel spring attached.
The swivel is lubricated by applying a drop of polysorbate 80 (Tween 80, United States Biochemical Corporation, Cleveland, OH 44128) to the rubber cap of the PRN adapter.
A stainless steel hypodermic needle connects the PRN adapter to the tube going to the animal (Fig. 2). The tube is protected from the animal by being enclosed within a flexible stainless steel spring (o.d. 0.155 inch 3.96 mm, i.d. 0.119 inch 3.00 mm; Projector Recording Belt Company, Whitewater, WI 58190) which is soldered to the stainless steel hypodermic needle. The swivel is mounted in a three-prong clamp so that the PRN adapter is the only part that turns. The swivel is cleaned as needed by flushing with warm water to remove any deposits that might impede flow. After each cleaning the swivel should be lubricated with polysorbate 80 so that it turns without excessive resistance. The swivel connector has been used successfully for chronic intragastric infusion of rats [5] and for chronic intracerebral infusion of mice (R. A. Selinfreund, Department of Anatomy, University of New Mexico Medical School, personal communication). Due to the relatively large dead space (0.33 ml), the swivel connector as described is less suitable for intravenous infusion of drugs. However, the following modification allows reduction of the dead space to approximately 0.10 ml. Remove the plastic liner holding the rubber cap on top of the PRN adapter and then remove the cap. Cut off 1.6 cm of the adapter and slide the rubber cap back on the shortened adapter. Stretch a small piece of teflon tape around the cap to hold it on tightly and to reduce friction.
ACKNOWLEDGEMENTS This work was supported by HEW-NIH grant 5-P-5OHP1132704 and by NIH grant 2507RRO7185-02.
REFERENCES I. Allsop, J. R. and J. F. Burke, Constant access to the circulation and intestinal tract of the unrestrained rat. J. Surg. Res. 25: l l l - l l 8 , 1978. 2. Altar, A. A chronic subcutaneous gastric cannula in adult rats. Pharmac. Biochem. Behav. 12: 629-631, 1980. 3. Darracq, C., P. Gonzalez and C. Balabaud. Double and single swivel joints for infusion and/or body fluid collections of free moving animals. Physiol. Behav. 25: 327-329, 1980. 4. Epstein, A. N. and P. Teitelbaum. A watertight swivel joint permitting chronic injection into moving animals. J. appl. Physiol. 17: 171-172, 1962.
5. Hayek, A., P. D. Bryant, L. Paxton and W. F. Woodside. Hypernatremia induces hypedipemia and a fatty liver. Clin. Res. 30: 137A, 1982. 6. Nicolaidis, S., N. Rowland, M.-J. Meile, P. Marfaing and A. Pesez. A flexible technique for long term infusion in unrestrained rats. Pharmac. Biochem. Behav. 2: 131-136, 1974. 7. Novin, D., M. Rezek and D. A. Vanderwelle. A cannula for infusion and withdrawal of fluids in unrestrained animals. Physiol. Behav. 12: 135-136, 1974. 8. Thomas, D. W. and J. Mayer. A simple and inexpensive swivel joint for the infusion of unrestrained animals. Physiol. Behav. 3: 499-500, 1968.