2016/01/01

Introducing Retinitis Pigmentosa Model (RCS) Rats | CLEA Japan, Inc.

CLEA Japan, Inc. provides RCS rats characterized by abnormal phagocytosis of photoreceptor cells by non-cutaneous cells on retinitis pigmentosa, recessive inheritance of retinal degeneration, and deletion degeneration of the Mertk gene.

Strain name :	RCS/Jcl-rdy/rdy	(homo)
Strain name :	RCS/Jcl-+/+	(wild)

Nomenclature:

・rdy homo	(p mutation exist)	= RCS-Mertk^rdyOca2^P/Jcl
・rdy wild	(p mutation exist)	= RCS-+Oca2^P/Jcl

Table of contents:

■ Characteristic

■ Origin

■ Research Field　　　　　　　　　　　　　　　　　　　　　　

■ Reference

▼Inquiry here

Characteristic

Widely used as a model for retinitis pigmentosa

Although the retina is formed normally after birth, degeneration of photoreceptor cells begins around 3 weeks after birth. Most photoreceptor cells disappear around the age of 3 months¹.
Abnormal phagocytosis of the outer segment of photoreceptor cells by retinal pigment epithelial cells².
It causes recessive inheritance of retinal degeneration³.
Has a defect in the Mertk gene⁴.

RCS rat retinal tissue image

In contrast to normal (left), 53-day-old RCS rat retina (right) shows thinning of photoreceptor cells (bar = 20㎛).

Reference:

1. Bourne M.C, Campbell DA, Tansley K. (1938) Br. J. Ophthalmol., 22, 613–622.

2. Mullen RJ LaVail MM. (1976) Science, 192, 799–801.

3. Bourne MC Gruneberg H. (1939) J. Hered., 30, 130–136.

4. Gal A, Li Y, Thompson DA, et al. (2000) Nat Genet, 26, 270-1.

Origin

1938		Bourne discovered a rat with a retinitis pigmentosa phenotype.
1981		LaVail (UCSF) established the animal as a specific strain.
1990		Dr. Tamai (Tohoku U.) made the strain as a Specific pathogen free (SPF) animal after supplied it from LaVail.
1994		RCS Research Committee inaugurated.
1994 to 2016		Japan had supplied RCS rat as a paid distribution animal.
2016		CLEA Japan, Inc. started to sell RCS rat as a general commercial animal.

Research Field

Photoreceptor protection

Protection of retinal degeneration by administration f growth factors

Basic fibroblast growth factor (bFGF, 1 µg / μl) was administered to the vitreous of 23-day-old RCS rats.

In the PBS-injected group, the photoreceptor layer has almost disappeared (left picture), whereas in the bFGF-injected group, the photoreceptor layer is observed (right picture), indicating that degeneration is delayed.

Reference：

Tamai M, Yamada K, Takeda N, et al. (1997) Degenerative Retinal, 323-328.

Retina reproduction study

Visual regeneration by optogenetics

The ChR2 gene is introduced into the ganglion cells of RCS rats that have lost their eyesight due to the disappearance of photoreceptor cells, and the visual function is regenerated. Retinal ganglion cells expressing ChR2 (green).