New Methodology for Investigating Ejaculation Dysfunction: Measuring Intraluminal Seminal Vesicle Pressure in Rats with a Telemetric Device.
BACKGROUND
Ejaculation dysfunction is one of the most common male sexual disorders. Despite its prevalence and adverse impact on patients, little attention has been given to investigating ejaculation dysfunction.


OBJECTIVE
We introduce a new method for evaluating ejaculation dysfunction in rats with a telemetric device.


METHODS
A pressure transducer was surgically implanted in the seminal vesicles of 7-week-old male Sprague-Dawley rats. One week later, the rats were subcutaneously administered tamsulosin 3 μg/kg, and intra-seminal vesicle pressure (ISVP) was recorded in freely moving rats after an injection of apomorphine (80 μg/kg). Same rats repeated experiment with tamsulosin 10 μg/kg, silodosin 1 mg/kg, and normal saline with 3-day intervals.


METHODS
Sexual events were visually identified and recorded. Ejaculation was confirmed by visualization of a copulatory plug in the tip of the penis. We compared the maximal ISVP and area under the curve (AUC) of the ISVP.


RESULTS
Adequate ISVP data were easily recorded and available in 66.6% rats (10/15) over a 6-week telemetric recording period (12 recordings). The mean number of ejaculations during an inspection time of 30 minutes was 1.5 ± 0.1. The maximal ISVP values in rats receiving 3 μg/kg (30.0 ± 5.2 mm Hg) and 10 μg/kg tamsulosin (15.1 ± 1.6 mm Hg) and 1 mg/kg silodosin (12.9 ± 2.2 mm Hg) were significantly lower than that in control rats (61.4 ± 13.4 mm Hg, P < 0.05). The AUC values in rats receiving 3 μg/kg (72.7 ± 18.9 mm Hg × s) and 10 μg/kg tamsulosin (23.5 ± 6.1 mm Hg) and 1 mg/kg silodosin (23.9 ± 8.0 mm Hg) were also lower than that of control rats (162.6 ± 34.3 mm Hg, P < 0.05).


CONCLUSIONS
Telemetric ISVP assessment is reliable and feasible for investigating apomorphine-induced ejaculation in rats. Tamsulosin (3 μg/kg and 10 μg/kg) and silodosin 1 mg/kg decreased the ISVP during ejaculation.
The Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
Hyun Hwan
HH
Sung
The Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jung Jun
JJ
Kim
The Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
Deok Hyun
DH
Han
The Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
Su Jeong
SJ
Kang
The Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
Mee Ree
MR
Chae
College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Korea.
Chul Young
CY
Kim
Department of Urology, Medical School, and Institute for Medical Sciences, Chonbuk National University, Jeonju, Korea.|Research Institute and Clinical Trial Center of Medical Device, Chonbuk National University Hospital, Jeonju, Korea.
Jong Kwan
JK
Park
The Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
Sung Won
SW
Lee
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D004195:Disease Models, Animal; D004542:Ejaculation / Q000187:drug effects*; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D010413:Penis / Q000473:pathology*; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D012669:Seminal Vesicles / Q000187:drug effects / Q000473:pathology*; D012725:Sexual Behavior; D013449:Sulfonamides / Q000494:pharmacology*; D000077409:Tamsulosin; D013686:Telemetry / Q000379:methods*; D064804:Urological Agents / Q000494:pharmacology*
D007211:Indoles; D013449:Sulfonamides; D064804:Urological Agents; C095285:silodosin; D000077409:Tamsulosin; D001058:Apomorphine
Apomorphine; Ejaculation Dysfunction; Telemetry; Telemetry Monitoring