Substance P-, F8Famide-, and A18Famide-like immunoreactivity in the nervus terminalis and retina of the goldfish Carassius auratus

Abstract

We re-investigated the occurrence of substance P-like immunoreactivity in the retina of the goldfish Carassius auratus using antisera to substance P and other tachykinins. Most antisera labelled a previously described single class of mono-stratified amacrine cells arborizing in layer 3 of the inner plexiform layer. Preabsorption experiments showed that these amacrine cells contained at least one tachykinin-like peptide. One antiserum (INC 353) to substance P labelled not only these amacrine cells but also fibres in layer 1 of the inner plexiform layer and fibres in the optic nerve. These fibres were identified as retinopetal projections of the nervus terminalis, in part because of colocalized labelling with antisera against gonadotropin-releasing hormone and FMRFamide. Preabsorption experiments showed that the substance P-immunoreactive material in the nervus terminalis was not substance P or any other typical tachykinin. Labelling of the nervus terminalis with INC 353 was blocked by preabsorption with two bovine FMRF-amide-like peptides, F8Famide and A18Famide, which contain a substance P(4-7)-like region. Antisera to F8Famide and A18Famide strongly labelled ganglia of the nervus terminalis and retinopetal fibres. We suggest that labelling of the nervus terminalis by antisera to substance P and FMRFamide occurs because of homologies between these antigens and a non-tachykinin, endogenous peptide that is similar to F8Famide and A18Famide.

Olfactoretinal centrifugal input modulates zebrafish retinal ganglion cell activity: a possible role for dopamine‐mediated Ca2+ signalling pathways

“…Thus, it is not clear what TN signals are received by DA‐IPCs and how the process of dopamine release is regulated. Furthermore, Fischer & Stell (1997) and Kyle et al (1995) reported that the RFamide‐like peptide released by the teleostean TN has a slightly different structure as compared to FMRFamide used in most of the previous experimental studies (Walker & Stell, 1986; Umino & Dowling, 1991). It is not clear whether the molluscan cardioexcitatory tetrapeptide FMRFamide can be expected to reproduce exactly the action of the endogenous RFamide‐like peptide.…”

“…Stell et al 1984; Umino & Dowling, 1991; Gastinger et al 2004). In goldfish, the application of molluscan cardioexcitatory tetrapeptide (a neuropeptide that has some resemblance to RFamide‐like peptide released by the teleostean TN; see Kyle et al 1995; Fischer & Stell, 1997) increased the firing rate of retinal ganglion cells (RGCs) (Stell et al 1984). In perch, the application of gonadotropin‐releasing hormone (GnRH, another neuropeptide contained in the TN; see Münz et al 1982; Stell et al 1984) depolarized horizontal cell membrane potentials and increased their responses to spots of light (Umino & Dowling, 1991).…”

Isolation and Identification of a Novel Fish Substance P and Its Effect on Retinal Cell Responses

“…In fish, SPRPs were isolated from the brain of cod, trout and dogfish (Jensen and Conlon, 1992;Waugh et al, 1993). In goldfish, SP-immunoreactivity was found in the brain (Sharma et al, 1989) and retina (Brecha et al, 1981;Kyle et al, 1995). Recently, Lin and Peter (1997) reported the isolation and sequencing of two cDNAs encoding for goldfish preprotachykinin (PPT).…”

Immunohistochemical and ultrastructural characterization of the terminal nerve ganglion cells of the ayu,Plecoglossus altivelis (Salmoniformes, Teleostei)

“…Apart from being immunopositive for the GnRH molecule, the TN ganglion cells (TNG cells) of teleosts are also positive for immunostaining with antisera against molluscan cardioexcitatory tetrapeptide (FMRFamide; Stell et al, 1984;Bonn andKonig, 1988,1989;Ekstrom et al, 1988;Ostholm et al, 1990;Uchiyama, 1990;%ma Krishna et al, 1992), substance P (SP; Stell et al, 1985;Alonso et al, 1989;Kyle et al, 19951, and neuropeptide Y (NPY;Magliulo-Cepriano and Schreibman, 1993;Subhedar et al, 1996). According to Kyle et al (1995), the substance of the goldfish TNG recognized by antisera to SP or FMRFamide is interpreted to be a nontachykinin endogenous peptide that is similar to FSFamide and A18amide. Furthermore, morphological and immunohistochemical studies have shown heterogeneity or subpopulations of the TNGiNOR cells in some acanthopterygian fishes: the filefish (Matsutani et al, 1986), the greenling (Uchiyama, 1990), and the dwarf gourami (Oka et al, 1986;Oka and Ichikawa, 1992).…”